Patient support apparatus communication systems

ABSTRACT

A location detection system for person support apparatuses includes multiple network wireless access points that communicate with a plurality of mobile transceivers positioned on board the person support apparatuses. Based upon signal strength data (e.g. RSSI or RCPI) of messages from the access points to the transceivers, the locations of the person support apparatuses are determined. In some embodiments, the person support apparatuses include an additional location detection system that utilizes fixed locators having short range transceivers to generate a second location determination of the person support apparatuses. In still other embodiments, the person support apparatuses utilize the second location detection system to determine the location of the wireless access points. The person support apparatuses may also broadcast their location to other devices that then utilize the received signal strengths of those messages to determine their own location.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 13/802,855 filed Mar. 14, 2013 by inventors Michael JosephHayes et al. and entitled PATIENT SUPPORT APPARATUS COMMUNICATIONSYSTEMS, which in turn claims priority to U.S. provisional patentapplication Ser. No. 61/640,138 filed Apr. 30, 2012 by applicantsMichael Hayes et al. and entitled PATIENT SUPPORT APPARATUSCOMMUNICATION SYSTEMS. The Ser. No. 13/802,855 patent application isalso a continuation-in-part application of U.S. patent application Ser.No. 13/680,699, filed on Nov. 19, 2012, by David T. Becker, et al.,entitled LOCATION DETECTION SYSTEM FOR A DEVICE, which is a continuationof U.S. patent application Ser. No. 13/356,204, filed Jan. 23, 2012, byDavid T. Becker, et al., entitled LOCATION DETECTION SYSTEM FOR APATIENT HANDLING DEVICE, which issued on Nov. 27, 2012, which is acontinuation of U.S. Pat. No. 8,102,254, which is a continuation of U.S.Pat. No. 7,598,853, which claims the benefit of U.S. provisional patentapplication Ser. No. 60/665,955, filed Mar. 29, 2005 and U.S.provisional patent application Ser. No. 60/734,083, filed Nov. 7, 2005.The subject matter of all of the aforementioned patents and patentapplications is incorporated herein by reference.

BACKGROUND OF THE INVENTION

The subject matter of this application relates to location systems formedical facilities. Location detection systems are known in the art fortracking the location of personnel and equipment in a facility. Thesesystems have been specifically adapted for use in facilities such ashealthcare facilities for tracking healthcare professionals, e.g.,nurses and physicians, and for tracking equipment, e.g., beds, patientmonitoring devices, and the like. A typical location detection system isalso referred to as an asset tracking system that utilizes tags thatperiodically transmit a unique identification signal. Receivers arelocated throughout the facility at known locations for receiving theseidentification signals. The receivers are wired to a central computerthat processes the unique identification signals to determine a locationof the asset associated with the tag.

The subject matter of the present application also relates to systemsand methods by which person support apparatuses—such as, but not limitedto, cots, stretchers, beds, chairs, recliners, operatingtables—communicate with each other and with other structures.

SUMMARY OF THE INVENTION

The present invention provides systems and methods for determining thelocation of person support apparatuses. In some embodiments, the systemsand methods allow a location of the person support apparatuses to bedetermined utilizing existing infrastructure of the healthcare facility,such as, but not limited to, wireless access points that are positionedat known locations throughout the healthcare facility. In someembodiments, the person support apparatuses communicate with each otherand share location information. In still other embodiments, the personsupport apparatuses communicate with other devices and share locationinformation with them. In still other embodiments, multiple technologiesfor determining the location of a person support apparatus are combinedtogether.

In one embodiment, a location detection system is provided that includesa person support apparatus and a controller. The person supportapparatus has a support surface and a wireless transceiver. The supportsurface is adapted to support a person thereon. The wireless transceiverwirelessly communicates with a plurality of access points of a computernetwork and receives messages from the plurality of access points. Thecontroller generates a location estimate of the person support apparatuswithin a facility based upon signal strength data of the messages fromthe plurality of access points.

In other embodiments, the messages include a media access control (MAC)address for each of the access points.

The wireless transceiver communicates with the access points, in atleast one embodiment, using a protocol that follows Institute ofElectrical and Electronics Engineers (IEEE) standard 802.11.

In other embodiments, the location detection system further includes aninfrared receiver adapted to receive an infrared signal from a fixedlocator positioned off of the person support apparatus. The infraredsignal includes a locator identifier unique to the fixed locator, andthe wireless transceiver transmits the locator identifier to one of theaccess points.

In some embodiments, the controller is positioned on the person supportapparatus, while in other embodiments the controller is positioned offthe person support apparatus and on the computer network.

In still other embodiments, the wireless transceiver is further adaptedto transmit the location estimate of the person support apparatus, asdetermined by the controller, to other devices. The other devicesinclude other person support apparatuses and/or other medical devices.

According to another embodiment, a location detection system is providedthat includes a person support apparatus, a processing station, and acontroller. The person support apparatus includes a frame, a supportsurface adapted to support a person thereon, and a wireless transceiveradapted to wirelessly communicate with a plurality of access points of acomputer network. The wireless transceiver is further adapted to receivemessages from the plurality of access points. The processing station islocated remotely from the person support apparatus and communicativelycoupled to the computer network. The controller is located on board theperson support apparatus and is adapted to send to the processingstation signal strength data of the messages.

In some embodiments, the processing station is further adapted to accessdata indicating locations of each of the plurality of access points, andto generate a location estimate of the person support apparatus within afacility based upon the signal strength data and the data indicatinglocations of each of the plurality of access points.

The controller sends the signal strength data to the processing stationusing the wireless transceiver, in some embodiments, and the processingstation includes map data indicating locations of the access pointswithin the facility.

In still other embodiments, the system includes an infrared transceiversupported on the person support apparatus and adapted to transmit aninterrogation signal, and a plurality of locators positioned at fixedlocations. Each of the locators is adapted to wirelessly transmit aunique identifier in response to the interrogation signal from theinfrared transceiver. The controller is adapted to send the uniqueidentifier to the processing station and the processing station isadapted to generate a location estimate of the person support apparatuswithin a facility based upon the unique identifier.

In some embodiments, the processing station is further adapted togenerate a location estimate of at least one of the access points basedupon the location estimate of the person support apparatus and thesignal strength data.

The processing station, in some embodiments, accesses data indicatinglocations of each of the plurality of access points, generates a firstlocation estimate of the person support apparatus based upon the signalstrength data and the data indicating locations of each of the pluralityof access points, and generates a second location estimate of the personsupport apparatus based upon the unique identifier.

In some embodiments, the processing station is further adapted togenerate a third location estimate of the person support apparatus bycombining the first and second location estimates.

The processing station is also adapted to forward at least one of thefirst and second location estimates to a second processing stationcommunicatively coupled to the computer network, in some embodiments.The processing station forwards the first location estimate to thesecond processing station if the person support apparatus is moving, andthe processing station forwards the second location estimate to thesecond processing station if the person support apparatus is stationaryand positioned adjacent to one of the locators. Still further, in someembodiments, the processing station forwards the first location estimateto the second processing station if the person support apparatus has abrake off, and the processing station forwards the second locationestimate to the second processing station if the person supportapparatus has the brake on.

The processing station is adapted to transmit the location estimate tothe person support apparatus, in some embodiments. In some embodiments,the controller is adapted to transmit the location estimate of theperson support apparatus wirelessly to another device.

According to another embodiment, a person support apparatus is providedthat includes a frame, a support surface adapted to support a personthereon, a first wireless transceiver, a second wireless transceiver,and a controller. The first wireless transceiver is adapted towirelessly communicate with a plurality of access points of a computernetwork and to receive messages from the plurality of access points. Thesecond wireless transceiver is adapted to wirelessly communicate with alocator positioned at a fixed location within a facility and to receivea unique identifier from the locator. The controller is adapted togenerate a location estimate of the person support apparatus within thefacility based upon signal strength data of the messages and/or theunique identifier.

The controller is further adapted to transmit the location estimate to aprocessing station located remotely from the person support apparatusand communicatively coupled to the computer network, in someembodiments.

The controller, in some embodiments, bases the location estimate of theperson support apparatus upon the signal strength data when a brake onthe person support apparatus is off.

According to other embodiments, a person support apparatus is providedthat includes a frame, a support surface, a first wireless transceiver,a second wireless transceiver, and a controller. The first wirelesstransceiver is adapted to wirelessly communicate with a plurality ofaccess points of a computer network and to receive messages from theplurality of access points. The second wireless transceiver is adaptedto wirelessly communicate with a locator positioned at a fixed locationwithin a facility and to receive a unique identifier from the locator.The controller is adapted to generate a location estimate of at leastone of the access points of the computer network based upon the uniqueidentifier.

In other embodiments, the person support apparatus includes a memory inwhich map data indicating a location of the locator is stored, and thecontroller uses the map data and signal strength data of the messageswhen generating the location estimate of the at least one of the accesspoints.

In some embodiments, the controller is further adapted to wirelesslyreceive location data from another person support apparatus that is incommunication with the at least one of the access points. The controlleruses the location data in generating the location estimate of the atleast one of the access points.

In other embodiments, the controller is further adapted to wirelesslytransmit the location estimate to another person support apparatus thatis in communication with the at least one of the access points.

In any of the embodiments disclosed herein, the person support apparatusmay be one of a bed, a stretcher, a cot, a recliner, and/or a chair, andthe computer network may be an Ethernet-based computer network.

Before the embodiments of the invention are explained in detail, it isto be understood that the invention is not limited to the details ofoperation or to the details of construction and the arrangement of thecomponents set forth in the following description or illustrated in thedrawings. The invention may be implemented in various other embodimentsand is capable of being practiced or carried out in alternative ways notexpressly disclosed herein. Also, it is to be understood that thephraseology and terminology used herein are for the purpose ofdescription and should not be regarded as limiting. The use of“including” and “comprising” and variations thereof is meant toencompass the items listed thereafter and equivalents thereof as well asadditional items and equivalents thereof. Further, enumeration may beused in the description of various embodiments. Unless otherwiseexpressly stated, the use of enumeration should not be construed aslimiting the invention to any specific order or number of components.Nor should the use of enumeration be construed as excluding from thescope of the invention any additional steps or components that might becombined with or into the enumerated steps or components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is side elevation diagram of a patient support apparatus intowhich one or more of the features of the present invention may beincorporated;

FIG. 2 is a diagram of one embodiment of an electrical control systemthat may be used with the patient support apparatus of FIG. 1, or withany of the other patient support embodiments described herein;

FIG. 3 is a plan view diagram of a plurality of patient supportapparatuses according to one embodiment showing a mesh network thatenables the patient support apparatuses to communicate with each otherand/or an access point of a healthcare network;

FIG. 4 is an plan view diagram similar to FIG. 3 showing how the meshnetwork may be used to forward information from patient supportapparatuses outside a range of the access point to one or more otherpatient support apparatuses that are within range of the access point;

FIG. 5 is a plan view diagram of an arbitrary portion of floor plan of ahealthcare facility that illustrates how some patient support apparatusembodiments may determine their location using triangulation techniquesof signals received from other patient support apparatuses;

FIG. 6 is a plan view diagram of another arbitrary portion of a floorplan of a healthcare facility that illustrates how some patient supportapparatus embodiments may transfer patient information from one patientsupport apparatus to another as a patient is transferred from onepatient support apparatus to another;

FIG. 7 is a plan view of a plurality of patient support apparatuses thatare configured to receive data from one or more medical devicespositioned within the vicinity of the patient support apparatuses, andto forward said data to a healthcare network access point;

FIG. 8A is a plan view of a mesh network arrangement of a plurality ofpatient support apparatuses wherein a potential data path from a firstpatient support apparatus to an access point of a healthcare network ishighlighted;

FIG. 8B is a plan view of the mesh network of FIG. 8A shown with onepatient support apparatus removed and an alternative data path fortransmitting data from the first patient support apparatus to the accesspoint of the healthcare network;

FIG. 9 is a diagram of an alternative electrical control system that maybe used with any of the patient support apparatuses described herein;

FIG. 10 is a plan view diagram of an arbitrary portion of a floor planof a healthcare facility showing patient support apparatuses that areconfigured to wirelessly receive and transmit medical data, patientdata, and other signals from other patient support apparatuses;

FIG. 11 is a schematic view of a healthcare facility with a network;

FIG. 12 is a top view of a typical room floor plan in the healthcarefacility with two zones labeled A and B, schematically illustrating alocation detection system embodiment utilizing a locator configured fortransmitting a unique location identifier to a receiver located on apatient handling device;

FIG. 13 is an electrical schematic of the locator of FIG. 12;

FIG. 14 is an electrical schematic of the receiver of FIG. 12;

FIG. 15 is a process flow diagram illustrating a process fortransmitting the unique location identifier from the locator to thereceiver;

FIG. 16 is a process flow diagram illustrating a process for requestingthe unique location identifier from the locator;

FIG. 17 is a perspective view illustrating alternative locationdetection systems utilizing radio frequency, magnetic inductance,ultrasonic, or modulated light systems;

FIG. 18 is a perspective view illustrating an alternative locationdetection system utilizing an array of RFID tags;

FIG. 19 is a perspective view illustrating an alternative locationdetection system utilizing an RFID swipe card;

FIG. 20 is a perspective view illustrating an alternative locationdetection system utilizing a tethered RFID magnet tag;

FIG. 21 is a perspective view illustrating an alternative locationdetection system utilizing a nurse call cable with an integrated RFIDtag;

FIG. 22 is a perspective view illustrating an alternative locationdetection system utilizing WiFi access points;

FIG. 23 is a perspective view illustrating an alternative locationdetection system utilizing a power cord with and integrated IDtransmitter;

FIG. 24 is a perspective view illustrating an alternative locationdetection system utilizing an Ethernet port to transmit the uniquelocation identifier;

FIG. 25 is a schematic view illustrating an alternative locationdetection system utilizing a mesh network to determine the location ofthe patient handling device;

FIG. 26 is a schematic view illustrating an alternative locationdetection system utilizing an asset tag in combination with a switch;

FIG. 27 is a schematic view illustrating an alternative locationdetection system utilizing an asset tag in combination with a sonicdistance finder;

FIG. 28 is a schematic view illustrating an alternative locationdetection system utilizing an asset tag in combination with a laserdistance finder;

FIG. 29 is a schematic view illustrating an alternative locationdetection system utilizing an asset tag in combination with a HallEffect sensing system;

FIG. 30 is a schematic view illustrating another alternative locationdetection system utilizing fixed wireless access points and a mobiletransceiver positioned on-board a person support apparatus;

FIG. 31 is a schematic view illustrating another alternative locationdetection system utilizing a combination of fixed wireless access pointsand fixed short range locators that communicate with correspondingtransceivers on-board the person support apparatus; and

FIG. 32 is a schematic view illustrating another alternative locationdetection system that includes person support apparatuses adapted tocommunicate location information to one or more separate devices.

DETAILED DESCRIPTION OF THE EMBODIMENTS

A patient support apparatus 20 that may incorporate one or more of theaspects of the present invention is shown in FIG. 1. Patient supportapparatus 20 may be a cot, a stretcher, a bed, a recliner, an operatingtable, or any other type of structure used to support a patient in ahealthcare setting. In general, patient support apparatus 20 includes abase 22 having a plurality of wheels 24, a pair of elevation adjustmentmechanisms 26 supported on said base, a frame 28 supported on saidelevation adjustment mechanisms, and a patient support deck 30 supportedon said frame. Patient support apparatus 20 further includes a headboard32 and a footboard 34.

Base 22 includes a brake (not shown) that is adapted to selectively lockand unlock wheels 24 so that, when unlocked, patient support apparatus20 may be wheeled to different locations. Elevation adjustmentmechanisms 26 are adapted to raise and lower frame 28 with respect tobase 22. Elevation adjustment mechanisms 26 may be hydraulic actuators,electric actuators, or any other suitable device for raising andlowering frame 28 with respect to base 22. In some embodiments,elevation adjustment mechanisms 26 are operable independently so thatthe orientation of frame 28 with respect to base 22 can also beadjusted.

Frame 28 provides a structure for supporting patient support deck 30,headboard 32, and footboard 34. Patient support deck 30 provides asurface on which a mattress (not shown), or other soft cushion ispositionable so that a patient may lie and/or sit thereon. Patientsupport deck 30 is made of a plurality of sections, some of which arepivotable about generally horizontal pivot axes. In the embodiment shownin FIG. 1, patient support deck 30 includes a head section 36, a seatsection 38, a thigh section 40, and a foot section 42. Head section 36,which is also sometimes referred to as a Fowler section, is pivotablebetween a generally horizontal orientation (not shown in FIG. 1) and aplurality of raised positions (one of which is shown in FIG. 1). Thighsection 40 and foot section 42 may also be pivotable, such as is shownin FIG. 1.

Although not illustrated in the patient support apparatus 20 depicted inFIG. 1, patient support apparatus will sometimes include a plurality ofsiderails (not shown) coupled to frame 28. If patient support apparatus20 is a bed, there are typically four such siderails, one positioned ata left head end of frame 28, a second positioned at a left foot end offrame 28, a third positioned at a right head end of frame 28, and afourth positioned at a right foot end of frame 28. If patient supportapparatus 20 is a stretcher or a cot, there are typically fewersiderails. In other embodiments, there are no siderails on patientsupport apparatus 20. Regardless of the number of siderails, suchsiderails are movable between a raised position in which they blockingress and egress into and out of patient support apparatus 20, and alowered position in which they are not an obstacle to such ingress andegress.

The construction of any of base 22, elevation adjustment mechanisms 26,frame 28, patient support deck 30, headboard 32, footboard 34, and/orthe siderails may be the same as disclosed in commonly assigned, U.S.Pat. No. 7,690,059 issued to Lemire et al., and entitled HOSPITAL BED,or as disclosed in commonly assigned U.S. Pat. publication No.2007/0163045 filed by Becker et al. and entitled PATIENT HANDLING DEVICEINCLUDING LOCAL STATUS INDICATION, ONE-TOUCH FOWLER ANGLE ADJUSTMENT,AND POWER-ON ALARM CONFIGURATION; or as disclosed in the StrykerMaintenance Manual for the Model 3002 S3 MedSurg Bed, available fromStryker Corporation of Kalamazoo, Mich., the disclosures of all three ofthese which are incorporated herein by reference. The construction ofany of base 22, elevation adjustment mechanisms 26, frame 28, patientsupport deck 30, headboard 32, footboard 34 and/or the siderails mayalso take on forms different from what is disclosed in theaforementioned documents.

Patient support apparatus 20 of FIG. 1 further includes a mesh networknode 84 that allows apparatus 20 to form an ad hoc electricalcommunications network with one or more other patient supportapparatuses 20 and/or one or more medical devices. Each of the otherpatient support apparatuses 20 and/or medical devices includes similarelectronics that form a mesh network node that is able to communicatewith node 84, as well as any other nodes 84 on other apparatuses 20 ormedical devices that are within communication range. Each node84—whether positioned on a patient support apparatus 20, a medicaldevice, or something else—is therefore able to not only disseminate datathat originates from the structure to which it is coupled, but also toserve as a relay for forwarding information it receives from other nodesonto to still other nodes, or onto a healthcare network 70 (FIG. 10), aswill be described in greater detail below. Further, because thepositions of patient support apparatus 20, as well as medical devicesand other structures, are likely to change over time, the mesh networkformed by the nodes 84 is dynamic such that the data paths change withchanging locations and/or other conditions.

FIG. 2 illustrates one embodiment of an electrical control system 44that is incorporated into patient support apparatus 20. Electricalcontrol system 44 includes, in the illustrated embodiment, an internalcommunications network 46. Internal communications network 46 is aController Area Network, although it will be understood by those skilledin the art that it could be another type of network, such as, but notlimited to, a CANOpen network, DeviceNet network, other networks havinga CAN physical and data link layer), a LONWorks network, a LocalInterconnect Network (LIN), a FireWire network, or any other knownnetwork for communicating messages between electronic structures onpatient support apparatus. Internal communications network 46 includes anumber of controllers or internal nodes that are in communication witheach other over the internal network 46. These include a footboardcontroller 48, an actuator/sensor controller 50, a scale systemcontroller 52, a first side rail controller 54, a second side railcontroller 56, a first transceiver controller 58, a second transceivercontroller 60, and a mattress controller 62. Before describing infurther detail the structure and functions of these controllers, itshould be pointed out that patient support apparatus 20 couldalternatively be designed without any internal communications network,but instead have various controllers communicate with each other in anon-networked manner, or by combining the functions of these variouscontrollers into one controller that handles all of these tasks, or instill other manners that do not utilize any sort of communicationsnetwork on the patient support apparatus 20.

Each controller that communicates over internal communications network46 includes one or more microprocessors, microcontrollers, fieldprogrammable gate arrays, systems on a chip, volatile or nonvolatilememory, discrete circuitry, and/or other hardware, software, or firmwarethat is capable of carrying out the functions described herein, as wouldbe known to one of ordinary skill in the art.

In the embodiment of FIG. 2, the electrical control system 44 of patientsupport apparatus 20 includes a first transceiver 64 that iselectrically and communicatively coupled to a first transceivercontroller 58, as well as a second transceiver 66 that is electricallyand communicatively coupled to second transceiver controller 60. It willbe understood by those skilled in the art that the use of the terms“first transceiver” and “second transceiver” herein has been done forcommunicative convenience, and that in no way do the “first” and“second” labels connote any significance to, or ranking of, therespective transceivers, nor are they intended to suggest a limit to thenumber of transceivers that may be present on a given patient supportapparatus 20.

First transceiver controller 58 is adapted to process messages that arecommunicated on electrical communications network 46 that are intendedfor first transceiver controller 58. Such messages will typically,although not exclusively, include messages containing data that is meantto be transmitted off of patient support apparatus 20 via firsttransceiver 64. Similarly, second transceiver controller 60 is adaptedto process messages that are communicated on electrical communicationsnetwork 46 that are intended for second transceiver controller 60. Suchmessages will typically, although not exclusively, include messagescontaining data that is meant to be transmitted off of patient supportapparatus 20 via second transceiver 66. First and second transceivercontrollers 58 and 60 are further adapted to process messages receivedby first and second transceivers 64 and 66, respectively, and, whereapplicable, forward the content of those messages onto internalcommunications network 46 for sharing with one or more of the variouscontrollers on network 46.

Together, first transceiver 64 and first transceiver controller 58 formmesh network node 84. Transceiver 64 therefore receives messages and/orsignals from other transceivers that are meant to be forwarded off ofpatient support apparatus 20, rather than consumed by patient supportapparatus 20. Controller 58 processes the received messages sufficientlyto determine whether the messages are for internal consumption orwhether they are to be relayed onto another recipient. Messages that areto be relayed are temporarily stored in memory that is accessible tocontroller 58 until such messages have been successfully forwarded ontoanother recipient. Messages that are to be consumed by patient supportapparatus 20 are processed by controller 58 and directly delivered tothe appropriate device on patient support apparatus 20 by hardwire orother direct connection, or their content is distributed via internalcommunications network 46 for use by one or more of the controllers onnetwork 46.

In one embodiment of patient support apparatus 20, first and secondtransceivers 64 and 66 are different types of transceivers. That is,each transceiver is adapted to transmit and receive electrical signalsusing two different communication protocols. For example, in oneembodiment, first transceiver 64 is adapted to transmit and receivewireless electrical signals using the ZigBee protocol, or the IEEE802.15.4 protocol, while the second transceiver 66 is adapted totransmit and receive wireless electrical signals using the Wi-Fiprotocol, or the IEEE 802.11 protocol. In other embodiments, firsttransceiver 64 uses the ZigBee or IEEE 802.15.4 protocol while secondtransceiver 66 is adapted to transmit and receive electrical signalsover a wire or cable connected to patient support apparatus 20. Such awire or cable may constitute a universal serial bus (USB) connection, orit may include an RS-232 or RS-485 connection, or it may include a wiredEthernet cable. In still other embodiments, still other communicationprotocols are used instead of those listed herein, whether wired orwireless, including, but not limited to, infrared communication,Bluetooth communication, and other types of communication.

Regardless of the specific communications format used, first transceiver64 is designed to communicate with one or more nearby structures, suchas, but not limited to, medical devices, sensing systems, and/or withother patient support apparatuses. First transceiver 64 therefore sendsmessages to and receives messages from medical devices equipped withtransceivers that are compatible with first transceiver 64, and/or itsends messages to and receives messages from sensing systems equippedwith compatible transceivers, and/or it sends messages to and receivesmessages from other first transceivers positioned on one or more otherpatient support apparatuses.

If communicating with another patient support apparatus, the otherpatient support apparatus need not be identical to patient supportapparatus 20, but instead merely has to be able to have the ability tosend and receive messages using the same protocol used by firsttransceiver 64. Thus, in some situations, if patient support apparatus20 is a bed, it is able to communicate via first transceiver 64 with astretcher, or with a cot, or a recliner, or some other type of patientsupport apparatus that is of a different physical type than a bed.Further, even if the other patient support apparatus is a bed, it neednot be constructed in the same manner as patient support apparatus 20.It may be a different model of bed in some cases, or it may be made by adifferent manufacturer in some cases, or it may be of the exact sametype of bed as patient support apparatus 20. The same is true if patientsupport apparatus 20 is a cot, a stretcher, a recliner, or somethingelse—the other patient support apparatuses to which it communicates viafirst transceiver 64 may be the same or a different type of patientsupport apparatus.

As noted, in some embodiments, first transceiver 64 is also configuredto communicate with one or more medical devices 110 (see, e.g. FIG. 7 or10). Such medical devices include any medical devices that are usable ina healthcare setting in a patient's room, or otherwise within a nearbyvicinity of a patient positioned on a patient support apparatus 20. Anon-exhaustive list of such potential medical devices includesventilators, vital signs monitors, respirators, infusion pumps, IVpumps, temperature sensors, and/or blood oxygen saturation monitors.When communicating with these medical devices, first transceiver 64 andits associated controller 58—which together form one mesh network node84—become part of a mesh network that includes other nodes 84. In suchcases, node 84 of support apparatus 20 is able to relay informationreceived from the medical devices 110 onto a healthcare communicationnetwork 70. This relay is able to take place via different routes.First, the relay of information may take place via a direct connectionbetween the support apparatus 20 and network 70, or this relay ofinformation may be routed through one or more other support apparatuses20 before it is delivered to network 70. These alternative routes areselected by the nodes 84 and intelligence shared between them regardingsignal strength, traffic, and/or other factors, as will be discussedmore below.

In still other embodiments, first transceiver 64 of patient supportapparatus 20 is configured to communicate with sensing systems that areused to sense one or more characteristics, features, conditions, and/orstates of the caregiver, the patient, or other personnel. For example,in one embodiment, such a sensing system includes an interface pressuresensing sheet position on top of a mattress on the patient supportapparatus 20, such as disclosed in commonly assigned U.S. patentapplication serial number PCT/US12/27402 filed Mar. 2, 2012 byapplicants Balakrishnan et al., and entitled SENSING SYSTEM FOR PATIENTSUPPORTS, the complete disclosure of which is incorporated herein byreference. In such an embodiment, first transceiver 64 is configured tocommunicate with any one or more of the sensor array 22, the controller24, the user interface 26, the sensor controller 28, and/or the tablet44 disclosed in the PCT/US12/27402 patent application. The data from theinterface pressure sensing system is forwarded via mesh network node 84of patient support apparatus 20 onto healthcare network 70, eitherdirectly from support apparatus 20, or via one or more additionalsupport apparatuses 20 or other types of intermediate mesh network nodes84. Still further, in some embodiments, the data from the interfacepressure sensing system is partially or wholly consumed by patientsupport apparatus 20, or a device positioned on patient supportapparatus 20.

In another embodiment, first transceiver 64 is configured to communicatewith a video monitoring system, such as that disclosed in commonlyassigned U.S. patent application Ser. No. 13/242,022 filed Sep. 23, 2011by applicants Derenne et al. and entitled VIDEO MONITORING SYSTEM, thecomplete disclosure of which is hereby incorporated herein by reference.In such an embodiment, first transceiver 64 is configured to communicatewith any one or more of the cameras 22, computer devices 24, and/orimage projectors 30 disclosed in the Ser. No. 13/242,022 patentapplication. The data from the video system and/or cameras is forwardedvia mesh network node 84 of patient support apparatus 20 onto healthcarenetwork 70, either directly from support apparatus 20, or via one ormore additional support apparatuses 20 or other types of intermediatemesh network nodes 84. Still further, in some embodiments, the data fromthe video monitoring system is partially or wholly consumed by patientsupport apparatus 20, or a device positioned on patient supportapparatus 20.

In still another embodiment, first transceiver 64 is configured tocommunicate with hand washing stations, or other devices, such asdisclosed in commonly assigned U.S. patent application Ser. No.13/570,934, filed Aug. 9, 2012, by applicants Hayes et al., and entitledPATIENT SUPPORT APPARATUS WITH IN-ROOM DEVICE COMMUNICATION, thecomplete disclosure of which is hereby incorporated herein by reference.In such an embodiment, first transceiver 64 is configured to communicatewith any of the electronic tags 24 (e.g. mobile tags 24 a, stationarytags 24 b, and patient tags 24 c) and/or the transceiver 52 disclosed inthe Ser. No. 13/570,934 application. The data from the hand washingstation, or other device, is forwarded via mesh network node 84 ofpatient support apparatus 20 onto healthcare network 70, either directlyfrom support apparatus 20, or via one or more additional supportapparatuses 20 or other types of intermediate mesh network nodes 84.Still further, in some embodiments, the data from the hand washingstation is partially or wholly consumed by patient support apparatus 20,or a device positioned on patient support apparatus 20. In yet otherembodiments, the patient hand washing station is configured to be, orinclude, a mesh network node itself, in which case the hand washingstation may be the recipient of data relayed off of patient supportapparatus 20 that is destined for communication to healthcare network70.

In still other embodiments, first transceiver 64 is configured tocommunicate with any combination of the devices disclosed herein,including, but not limited to, any of those disclosed in the patentreferences incorporated herein by reference. Still further, patientsupport apparatus 20 may be modified to include a third or fourthtransceiver that, instead of, or in addition to, first transceiver 64,communicates with any of the devices disclosed herein, including, butnot limited to, any of those disclosed in the patent referencesincorporated herein by reference.

Second transceiver 66, as noted earlier, is configured to communicatewith one or more wireless access points 68 of a healthcarecommunications network 70. An example of one such communications network70 is shown in FIG. 10. Such a network is often an Ethernet network,although it may use other networking communication protocols. Thedevices, applications, and/or servers that are coupled to the network 70will vary from facility to facility because they will be dependent upona particular healthcare institution's choice of what third-partysoftware and/or systems they have installed on their network. In theillustrative embodiment shown in FIG. 10, network 70 includes aplurality of nurses stations 72, tablet and/or phones 74, computers onwheels (COW) 76, work stations 80, and one or more personal computers82. An electronic medical records (EMR) server or system 78 may also beincluded. As noted, network 70 may further include one or moreadditional devices, applications, and/or servers, or it may include oneor fewer devices, applications, and/or servers, depending upon theparticular configuration that has been implemented at a particularhealthcare facility. Such additional devices, applications, and/orservers may include an Admission, Discharge, and Transfer (ADT) systemthat manages the admission, discharge, and transfer of patients in thehealthcare facility; a workflow server that manages the work assignmentsof caregivers in the healthcare facility; and/or wireless alertingsystem that automatically forwards alarms and alerts to appropriatehealthcare personnel via wireless communication technology. Suchwireless communication technology may include the forwarding of alertsvia cell phones, WIFI devices, pagers, personal digital assistants(PDAs), or by other means. Any information that is transmitted tonetwork 70 via one or more of the mesh network nodes 84 may thereforecause an alert to be forwarded to the appropriate caregiver(s),depending upon the contents of such information. The nurses station 72,tablets 74, computers on wheels 76, work stations 80, personal computers82, electronic medical record systems 78, ADT systems, work flowsystems, and wireless alerting systems may all be conventional productsthat are commercially available from one or more different suppliers, aswould be known to one of ordinary skill in the art.

FIG. 3 illustrates an arbitrary example of a mesh network 86 thatcreated by a plurality of patient support apparatuses and theirrespective mesh network nodes 84. In the example shown, the mesh network86 includes four patient support apparatuses 20 that are beds (20 a, 20b, 20 c, and 20 d), one patient support apparatus 20 that is a stretcher(20 e), and one patient support apparatus 20 that is a cot (20 f). Eachpatient support apparatus 20 includes a mesh network node 84 thatcomprises first transceiver 64 and first transceiver controller 58. Eachnode 84 broadcasts signals that are responded to by all of the othernodes that are sufficiently close to receive the broadcasted signals.This broadcasting and responding enables each patient support apparatus20 to determine what other patient support apparatuses 20 are withincommunication distance. When responding to such broadcasts, a node 84also responds with information identifying what nodes 84 it itself is incommunication distance with. For example, if stretcher 20 e sends out aninitial broadcast, beds 20 a, 20 b, and 20 d, along with cot 20 f, willrespond because they are all sufficiently close to be withincommunication range of stretcher 20 e (for purposes of discussion, itwill be assumed that bed 20 c is out of direct communication range withstretcher 20 e). The response from beds 20 a, 20 b, and 20 d and cot 20f includes information indicating the nodes that each of theseapparatuses 20 are in communication with. Thus, for example, bed 20 amight respond to stretcher 20 e by indicating that it is able tocommunicate with bed 20 b, bed 20 c, cot 20 f, and bed 20 d. Similarly,bed 20 d might respond to stretcher 20 e by indicating that it is ableto communicate with beds 20 a, 20 b, and 20 c, as well as cot 20 f.Still further, in addition to forwarding information about what nodes aparticular node is currently able to communicate with, informationidentifying the relative signal strengths of each of the currentlyavailable nodes is also included. In this manner, routing of theinformation can be accomplished by selecting routes having relativelyhigher signal strengths, or at least signal strengths above apredetermined threshold, thereby ensuring that more bandwidth isavailable for transmitting information.

In some embodiments, the response back to stretcher 20 e also includesinformation indicating whether any of the nodes 84 are able tocommunicate with a wireless access point 68 of healthcare network 70.Thus, for example, bed 20 a might respond to stretcher 20 e byindicating that not only is it able to communicate with beds 20 b, 20 c,and 20 d, and cot 20 f (and also their signal strengths), but also thatbed 20 b is able to communicate directly with a wireless access point68, which, in the example of FIG. 3, is a WiFi access point, although itwill be understood by those skilled in the art that other types ofaccess points could be used. Because beds 20 c and 20 d, as well as cot20 f, are all in communication with bed 20 b, they too might all respondto stretcher 20 e with information indicating that bed 20 b is indirection communication with access point 68. Each apparatus 20 istherefore able to include in its response to stretcher 20 e anindication that it is or that it is not is direct communication with awireless access point, as well as a similar indication for all of theapparatuses it is in communication with. Depending upon the size of themesh network 86, additional levels of communication abilities may beprovided for nodes 84 that are even further downstream from stretcher 20e.

In addition to responding to stretcher 20 e's initial broadcast, eachapparatus 20 that is within communication distance may also respond withadditional information that may be useful for stretcher 20 e. As wasnoted, such additional information may include information about thesignal strength of each of the communication channels betweenapparatuses 20, and/or the signal strength between an apparatus 20 andan access point 68. Such additional information alternatively, oradditionally, includes information indicating a current level ofcommunication traffic and/or information backlog and/or availablebandwidth and/or the congestion that a node is experiencing. Stillfurther, such information includes information that uniquely identifieseach node, and/or information that uniquely identifies each patientsupport apparatus 20.

All of the information that stretcher 20 e receives in response to itsinitial broadcast message is stored in a memory accessible to firsttransceiver controller 58. This information enables controller 58 todetermine which route, or portion of a route, is the best route fortransmitting data to access point 68. That is, stretcher 20 e uses theinformation it receives from the other nodes (e.g. 84 a, 84 b, 84 d, and840 to select an initial recipient of any data that it needs to forwardto network 70 (which would be via access point 68 in FIG. 3, althoughthere may be multiple access points in other examples). Once thisinitial recipient is chosen, node 84 e of stretcher 20 e transmits thedesired information to that recipient, which then forwards theinformation onto access point 68, either directly or by some otherroute, depending upon circumstances. In some embodiments, the originalsource of the transmitted information (in this example, stretcher 20 e)includes information indicating its preferred complete routing path toaccess point 68, while in other embodiments, the original source of thetransmitted information only chooses the initial recipient of thetransmitted data and leave subsequent routing decisions to thediscretion of the recipient node and any other downstream nodes thatrelay the information to access point 68.

As was noted, the choice of the initial recipient of the information ismade based upon any one or more of the items of information receivedfrom the other nodes. The choice of the initial recipient may also becombined with predefined data or programming instructions. Suchpredefined data or programming instructions may, for example, dictatethat, absent extenuating circumstances, an apparatus 20 will try tocommunicate information to access point 68 in the most direct route(i.e. the route involving the fewest number of communications hopsbetween the source of the data and network 70). Thus, as an example,stretcher 20 e may be programmed to initially select by default bed 20 bas the initial recipient of its transmitted data because bed 20 b is indirect communication with access point 68. However, such programmingcould also take into account the signal strength of the communicationpath 88 between stretcher 20 e and bed 20 b and, if it is below adesired threshold level, cause node 84 e to seek an alternate initialrecipient with which it has a communication path 88 having a strongersignal. Stretcher 20 e may therefore, as an example, determine that path88 between stretcher 20 e and bed 20 b is too weak, and therefore chooseto initially send its data to bed 20 a. This choice of bed 20 a as analternative to the default initial recipient may be based upon any ofthe information stretcher 20 e has received from the other nodes 84.Thus, the choice of bed 20 a as the alternative initial recipient of thedata from stretcher 20 e may be made, for example, because thecommunication path 88 between stretcher 20 e and bed 20 a is strongerthan any of the other communication paths stretcher 20 e has with theother patient support apparatuses 20 c, 20 d, and 20 f.

The data that is able to be transmitted from a patient support apparatus20 includes a variety of different types of data, some of which will bediscussed in greater detail below. In some embodiments, data about oneor more sensors and/or systems on the patient support apparatus 20 iscommunicated. Such data includes information indicating whether the siderails of a patient support apparatus are up or down; whether the brakeis locked or unlocked; the height of the frame 28 or patient supportdeck 30 above the base 22 (in those apparatuses where this height can bechanged by a user); the angle of one or more sections of deck support 30(such as head section 36—which may be useful to know for helping toprevent ventilator associated pneumonia and/or for other purposes); theoutput from a bed exit system that is incorporated into patient supportapparatus 20 (such as, but not limited to, the bed exit system disclosedin commonly-assigned U.S. Pat. No. 5,276,432 issued to Travis andentitled PATIENT EXIT DETECTION MECHANISM FOR HOSPITAL BED, the completedisclosure of which is hereby incorporated herein by reference);information indicating whether a bed exit system is armed or disarmed;the output from a patient movement detection system that is incorporatedinto patient support apparatus 20 (such as, but not limited to, thepatient movement detection system disclosed in commonly-assigned U.S.Pat. No. 6,822,571 issued to Conway and entitled PATIENT MOVEMENTDETECTION SYSTEM FOR A BED INCLUDING A LOAD CELL MOUNTING ASSEMBLY, thecomplete disclosure of which is also incorporated herein by reference);the output from a patent interface pressure detection system (such as,but not limited to, that disclosed in the PCT/US12/27402 applicationfiled Mar. 2, 2012, discussed above); data from one or more medicaldevices that are either supported on apparatus 20, or in communicationwith apparatus 20 (such as via first transceiver 64); information from avideo monitoring system (such as that disclosed in the Ser. No.13/242,022 patent application mentioned above); and information fromother devices or structures in the room that have wireless communicationabilities (such as, but not limited to, the devices disclosed in theSer. No. 13/570,934 application discussed above.

Any of the data that is transmitted from a patient support apparatus 20is data that originates from that particular patient support apparatus,or it is data that is received from another patient support apparatus 20that is to be relayed onto another node 84 or an access point 68.Regardless of whether the data that is to be transmitted originates fromthe support apparatus 20, or was received from another support apparatus20, the algorithms used for determining the next recipient of the dataare the same. Thus, for example, in the arbitrary example discussedabove with respect to FIG. 3 wherein stretcher 20 e is transmitting datathat is to be forwarded to access point 68, the logic used by stretcher20 e to determine the initial recipient of its data is the same,regardless of whether the transmitted data originated from stretcher 20e, or it was received by stretcher 20 e from another support apparatus(such as, for example, bed 20 d). Similarly, once stretcher 20 etransmits the data to an initial recipient (e.g. bed 20 a), thatrecipient utilizes the same logic and/or algorithms that stretcher 20 eused in deciding what node to forward the data to.

By forwarding information through mesh network 86 to access point 68,the information is able to avoid bottlenecks, route around weakcommunication channels, and in some cases (such as discussed below withrespect to FIG. 4) avoid areas where communication with access point 68is not possible. The routing algorithms used therefore ensure that datais efficiently, yet effectively, transferred to the healthcare network70 so that the appropriate servers and/or applications on the network 70can used the transmitted data in the desired manner.

FIG. 4 illustrates another arbitrary example wherein some of the patientsupport apparatuses 20 and associated nodes 84 are completely outsidethe communication range of access point 68. In the example of FIG. 4, aboundary line 90 indicates the furthest extent of the communicationrange of access point 68. Thus, only beds 20 b and 20 c are withincommunication range of access point 68. Any information to betransmitted from beds 20 a and 20 d, or cot 20 f and stretcher 20 e tonetwork 70 must therefore pass (in this example) through either bed 20 bor bed 20 c. By enabling patient support apparatuses 20 to communicateover, and form, a mesh network 86, the communication range of accesspoint 68 is effectively extended. That is, because those apparatuses 20within range of access point 68 (e.g. beds 20 b and 20 c) can talk toapparatuses outside of range 90 and relay information from theseapparatuses 20 to access point 68, the effective communication range ofaccess point 68 is enlarged. This allows healthcare facilities to avoidthe expensive extra infrastructure that might otherwise be necessary toprovide sufficient communication abilities throughout a facility (i.e.it may not be necessary to install as many wireless access points 68 ina given facility when the facility uses the mesh-network equippedpatient support apparatuses 20 disclosed herein).

When a patient support apparatus 20 is forwarding data to network 70 viamesh network 86 and there are multiple patient support apparatuses 20 indirect communication with one or more access points 68 (such as, forexample, the situation illustrated in FIG. 4), the choice of whichapparatus 20 to forward data to may be made in the same manner asdiscussed above. That is, in the example of FIG. 4, the choice betweenrouting data through bed 20 b or 20 c is based upon one or more of thefollowing: a default preferred path, relative signal strengths,available bandwidth, traffic congestion, communication backlogs, and/orother factors. If such factors present an equal case for routing throughbeds 20 b and 20 c, then the ultimate choice may be based on a randomselection, or some other factor.

In the examples of FIGS. 3 and 4, the data transmitted from a supportapparatus 20 to access point 68 has been ultimately transmitted toaccess point 68 via a second transceiver 66 on one of patient supportapparatuses 20. If that data has been received from another patientsupport apparatus 20 (and is thus being relayed to access point 68), thereceipt of data is via first transceiver 64. Thus, mesh networkcommunications is accomplished via first transceivers 64, whilecommunications with one or more access points 68 is via secondtransceivers 66.

It will be understood by those skilled in the art that all of the firsttransceivers 64 do not have to be identical to each other. Similarly, itwill be understood by those skilled in the art that all of the secondtransceivers 66 do not have to be identical to each other. If disparatetypes of first and/or second transceivers 64 and/or 66 are incorporatedinto the support apparatuses 20 of a given mesh network 86, then thecommunication abilities of the transceivers may also be relayed to eachof the nodes and used in the algorithms for determining routing. Forexample, in some embodiments, some patient support apparatuses have asecond transceiver 66 that is able to communicate in accordance withIEEE 802.11b standards, while other patient support apparatuses 20 areable to communicate in accordance with IEEE 802.11g or 802.11nstandards, both of which are faster than 802.11b standards. Thisinformation is factored into the algorithms for choosing the mostefficient routing of data to network 70.

Mesh network 86 is also useful for disseminating data from one or moresources on healthcare network 70. When disseminating such data, the sameor similar algorithms can used for routing the data through mesh network86 to the appropriate destination. Such disseminated data includes, butis not limited to, patient information (such as, but not limited to,information that identifies a particular patient who is occupying aparticular patient support apparatus), caregiver information (such as,but not limited to, information identifying the what caregiver(s) havebeen assigned to a particular patient, room, or support apparatus 20),medical information (such as, but not limited to, information about thefall risk or a patient, information about the susceptibility of apatient to bed sores—such as a Braden scale rating, information and/orany other relevant medical information about a particular patient),commands (such as, but not limited to, commands to change the status ofa system or component on patient support apparatus 20), requests fordata, acknowledgements, and/or any other type of data that is desirablycommunicated to one or more patient support apparatuses 20, or to any ofthe devices or other structures that a patient support apparatus 20 isin communication with via one or more of its transceivers.

Each node 84 of mesh network 86 is configured to dynamically andregularly update its communication abilities and/or status so that therouting of data through mesh network 86 is dynamically adapted tochanging conditions. Such changing conditions can include, for example,the movement of one or more patient support apparatuses 20 to differentlocations, traffic congestion, the addition or deletion of one or moredata sources or destinations (e.g. one or more medical devices orsupport apparatuses 20), and/or any other conditions that might usefullyinfluence the efficient routing of data through mesh network 86.

FIGS. 8A and 8B illustrate one example in which a mesh network 86dynamically updates itself when a patient support apparatus 20 exits themesh network 86. In the example of FIG. 8A, a bed 20 u is communicatingdata to a bed 20 v via two intermediate patient support apparatuses 20;namely, a bed 20 w and a stretcher 20 x. The information is beingtransmitted through nodes 84 w and 84 x of these two intermediatesupport apparatuses 20. This data path, however, may change, such as,for example, by the movement of one or both of support apparatuses 20 wand/or 20 x. In the example of FIG. 8B, stretcher 20 x has been moved toa new location that is outside of mesh network 86. In order for patientsupport apparatuses 20 u and 20 v to continue to communicate, a new datapath is automatically created by mesh network 86. In the example of FIG.8B, the new data path is from bed 20 v to bed 20 w to bed 20 y to bed 20v, and/or the reverse. By dynamically changing the routing of data whenone or more nodes 84 are either added or removed from mesh network 86,communication can still be accomplished without interruption.

Alternatively, or in addition to, the data transfer abilities of meshnetwork 86 described above, some embodiments of patient supportapparatuses 20 are configured to use mesh network 86 to determine theirlocation within a healthcare facility. This is especially useful forhealthcare facilities where some apparatuses 20 are not able todetermine their location at all times, such as, for example, duringmovement of the apparatus 20 from one location within the facility toanother location within the facility. FIG. 5 illustrates one manner inwhich mesh network 86 is used to determine the location of one or morepatient support apparatuses. Specifically, stretchers 20 g and 20 h areshown in a corridor or hallway 92 within an arbitrary portion of ahealthcare facility 98. Stretcher 20 g includes a mesh network node 84 gwhile stretcher 20 h includes a mesh network node 84 h. These nodes 84 gand 84 h are able to wirelessly communicate with other nodes 84 that arewithin a vicinity of these nodes (the size of the vicinity will dependupon the specific communication protocol and/or standards used by nodes84, as well as the communication and reception power of the electronicsin nodes 84). Nodes 84 g and 84 h (as well as, in some cases, the nodes84 on beds 20 i, 20 j, 20 k, 201, 20 m, and 20 n) are adapted todetermine their location by using triangulation techniques, ortrilateration techniques, or some combination of the two, with the othernodes 84 that are within communication range. Such triangulationtechniques will enable the nodes to calculate their relative position tothe other nodes that are within communication range. If one or more ofthe other nodes that are within communication range knows its absolutelocation within health care facility 98, or otherwise possessesinformation that enables its absolute location to be determined withinfacility 98, then those other nodes that know their relative location tothese nodes are able to calculate their absolute position within thefacility.

If configured to determine location based upon triangulation, each node84 g and 84 h includes one or more antennas that are adapted todetermine the direction in which signals from the other nodes 84 arereceived at nodes 84 g and 84 h, respectively. Such antennas and/orother equipment may be conventional equipment, as would be known to oneof ordinary skill in the art. If a node (e.g. 84 g and/or 84 h) receivessignals from a sufficient number of other nodes, the angular informationdetermined from those signals will be sufficient for the node (84 g or84 h) to determine its relative location to the patient supportapparatuses 20 from which it received signals. This relative positioncan be converted into an absolute position within the healthcarefacility if the absolute positions of the patient support apparatusesthat transmit signals to nodes 84 g and/or 84 h are known. In someembodiments, this conversion of relative position to absolute positionis performed by one or more processors located on the patient support 20itself, while in other embodiments, it is performed by a server orapplication that is running on healthcare network 70.

FIG. 5 illustrates an example of how, in one embodiment, stretcher 20 gdetermines its location using triangulation techniques. By determiningthe direction from which signals are received from nodes 84 on patientsupport apparatuses 20 i and 20 j, which are in rooms 2 and 4,respectively, node 84 g will be able to determine a first angle 94 (FIG.5). By determining the direction from which signals are received fromthe nodes 84 on patient support apparatuses 20 j and 20 m, which are inrooms 4 and 3, respectively, node 84 g will also be able to determine asecond angle 96 (FIG. 5). Further, because the locations of beds 20 i,20 j, and 20 m is already known—as determined in any conventionalmanner, at least one of which is described in greater detail below—node84 g on patient support apparatus 20 g is able to determine its absolutelocation within healthcare facility 98. The relative signal strength ofall of the received signals may also be used in determining location.

It will be further understood by those skilled in the art that thedetermination of the location of a patient support apparatus 20 (such asstretcher 20 g in FIG. 5) within a given facility 98 may be, in someembodiments, a determination of an approximate location. For example,the algorithms used to determine location may, in some embodiments,specify the location of the patient support apparatus merely to thelevel of a room or a portion of a room, or a corridor or hallway, or asection of a corridor or hallway, or some other generalized area.However, it will also be understood that finer levels of positiongranularity are determined in some embodiments.

If nodes 84 are equipped to determine location using trilateration ormultilateration techniques, either in lieu of, or in addition totriangulation techniques, nodes 84 may be configured to determine thetime it takes for signals from other nodes 84 to travel to the nodewhose destination is being determined. Such time of flight measurementsor computations can be used to determine distances between nodes 84.This will enable a node 84 to determine its relative location. Further,if some of the absolute positions of the nodes are known, the relativeposition may be converted into an absolute position within thehealthcare facility 98.

In one embodiment, some of the patient support apparatuses 20 are ableto determine their location within a healthcare facility 98 by way of alocation system that utilizes a plurality of stationary modules 100 andstationary module transceivers 102. The stationary modules 100 arepositioned on walls, ceilings, or in other fixed locations whoseabsolute positions within the healthcare facility 98 are known. Themodule transceivers 102 are incorporated into some or all of the patientsupport apparatuses 20. In the example of FIG. 2, the electrical controlsystem 44 of patient support apparatus 20 has transceivers 102 feedinginto, and controlled by, actuator/sensor controller 50. It will beunderstood by those skilled in the art that transceivers 102 may becontrolled by other controllers, and/or integrated into a patientsupport apparatus in different manners. Further, as will be discussed ingreater detail, stationary modules 100 and stationary moduletransceivers 102 are configured the same as locators 252 and receivers254, respectively, in at least some embodiments, or the same as locators444 and transceivers 440, respectively, in still other embodiments.

In one embodiment, a healthcare facility may have a plurality of patientsupport apparatuses 20 that are beds that include such transceivers 102,while other types of patient support apparatuses 20—such as stretchers,cots, and the like—might not include such module transceivers 102.Regardless of which specific patient support apparatuses 20 have moduletransceivers 102 incorporated therein, any such apparatus 20 having amodule transceiver 102 incorporated therein will be able to communicatewith a fixed module 100 when the apparatus is within a relatively closeproximity thereto. Such proximity may be on the order of five to tenfeet, or it may be other distances. In some embodiments, moduletransceiver 102 communicates with modules 100 via infrared signals,although it will be understood by those skilled in the art that othertypes of signals may be used for communication between modules 100 andtransceiver 102.

In general, because the locations of modules 100 is known, and becausethe patient support apparatuses can only communicate with a given module100 (via transceivers 102) then they are within a close proximity to thegiven module 100, the very establishment of such communication indicatesthat the patient support apparatus 20 is in close proximity to a givenmodule 100 whose location is known. This allows the location of apatient support apparatus 20 to be determined.

In one embodiment, modules 100 are configured to respond tointerrogations received from transceiver 102 with an identifier thatuniquely identifies and distinguishes that particular module 100 fromall other such modules 100 within the healthcare facility 98. Thepatient support apparatus 20 includes a map, table, or other informationthat correlates that specific module 100 to a known location, or itcommunicates with an application or server on network 70 that maintainssuch a map, table, or other information. In either case, the patientsupport apparatus is able to determine its location. Further details ofthe operation of modules 100 and transceivers 102, as well as the mannerin which they can be used to determine location, are found in commonlyassigned, copending U.S. patent application Ser. No. 12/573,545 filedOct. 5, 2009 by applicants David Becker et al. and entitled LOCATIONDETECTION SYSTEM FOR A PATIENT HANDLING DEVICE, the complete disclosureof which is also incorporated by reference herein.

If a location system such as the one just described (i.e. having modules100 and transceivers 102) is used within a healthcare facility, it iscustomary to only position such modules 100 near locations where bedsare likely to be stationed or parked (i.e. at the location in a roomwhere the bed normally resides, or, if in a multi-bed room, at eachlocation where the bed is normally parked). Such modules 100 are nottypically placed in hallways or other locations where the beds or otherpatient support apparatuses are temporarily moved. The aforementionedtriangulation and/or trilateration techniques used with nodes 84 maytherefore be used to determine location when a patient support apparatus20 is not within an operational vicinity of a module 100. Further, theaforementioned triangulation and/or trilateration techniques may be usedwith those patient support apparatuses 20 that might not be equippedwith a location transceiver 102. Nodes 84 therefore complement existinglocation determining systems and/or fill in gaps in those existinglocation determining systems so that greater location knowledge—in termsof both coverage throughout the facility and/or in terms of the numberof patient support apparatus—is achievable within a healthcare facility.The location information determined by way of nodes 84 is stored locallyon the respective patient support apparatus 20 and/or it is forwarded tohealthcare network 70 to one or more servers and/or applications runningon the network 70. The forwarding of such information takes place usingone or more mesh networks 86 in the manners described above, or it takesplace via a direct communication with an access point 68 of network 70,or by other means.

In some embodiments, patient support apparatuses 20 that are notequipped with location transceivers 102 are, after determining their ownlocations, used to help determine the location or locations of otherpatients, or other patient support apparatuses 20 that are also notequipped with location transceivers 102, or that are equipped with suchtransceivers 102 but are currently located outside the vicinity of amodule 100. For example, if stretcher 20 g in FIG. 5 determines itslocation using its node 84 g and one of the triangulation and/ortrilateration techniques discussed above, node 84 g is configured torespond to signals from node 84 h of stretcher 20 h that are being sentby node 84 h to determine the location of stretcher 20 h. In otherwords, node 84 h of stretcher 20 h is thereafter able to measure itsangular relationship and/or its distance to stretcher 20 g whendetermining its location. Thus, once a patient support apparatus 20 usesits node 84 to determine its location, it serves as a source of locationinformation for other patient support apparatuses 20. In this way, it ispossible to extend location determination abilities farther and fartheraway from modules 100. Or, stated alternatively, the nodetriangulation/trilateration position determining system described hereinaugments any existing location system, and may be cascaded upon itselfso that patient support apparatuses that can only communicate via nodes84 with other patient support apparatus 20 that themselves are outsidethe range of modules 100 can still determine their location.

The node triangulation/trilateration position determining systemdescribed herein may also be used with a position determining systemthat is based upon WIFI signals and the known location of thecorresponding routers, access points, and/or other stationary structuresthat communicate those WIFI to and from the mobile patient supportapparatuses 20. For example, if a patient support apparatus 20 iscommunicating with a specific access point 68 via second transceiver 66,that patient support apparatus 20 may be configured to determine itsgeneral location as being within a general range of the access point 68.This general range is then further refined by way of thetriangulation/trilateration techniques described above. Further, thistriangulation/trilateration technique is able to be used to extend therange at which patient support apparatus 20 is capable of determine itslocation beyond the communication range of the access point 68. Indeed,the range may be extended—depending upon the location of patient supportapparatuses 20—to locations where there are no available access points68.

The patient support apparatus to patient support apparatus communicationthat has so far been described can be used for two separate andpotentially independent purposes. First, as was described previously,this communication may be used to create mesh networks for betterrouting of information between patient support apparatuses 20 and ahealthcare network 70. Second, as was also just described above, thispatient support apparatus to patient support apparatus communication maybe used to determine location and/or to augment or complement thelocation determining abilities of another patient support apparatuslocation determining system. As will be described below with referenceto FIG. 6, this patient support apparatus to patient support apparatuscommunication may be used for yet another purpose: transferring patientinformation between patient support apparatuses.

In lieu of, or in addition to, either of the mesh networking andposition determining functions of nodes 84, such nodes are also usefulfor storing and transferring patient information, medical information,or other information between patient support apparatuses 20. That is,nodes 84 are configured to store information about the patient that iscurrently being support on the support apparatus 20. This information isreceived via transceivers 64, or by any of the other transceiverspositioned on support apparatus 20. Further, the storage of thisinformation may be in a memory within node 84, or it may be in anotherlocation on the patient support apparatus 20. Regardless of the sourceof the information and regardless of its storage location on the patientsupport apparatus, the information includes personal information and/ormedical information about the patient being supported on apparatus 20.For example, the information may include the patient's name, height,weight, allergies, fall risk assessment, bed sore risk assessment,and/or any other medical or personal information that may be usefullystored on the support apparatus.

In some patient support apparatus embodiments, the stored information isdisplayable on an LCD screen, touchscreen, or other type of display onthe patient support apparatus so that caregivers will have visual accessto the information. The patient support apparatus 20 may also beconfigured to transmit the information locally to a pendant supported onpatient support apparatus 20, or to a medical device that is pluggedinto, or otherwise communicatively coupled, to patient support apparatus20. In such cases, the pendant and/or medical device are configured todisplay the information. In still other embodiments, the patient supportapparatus wirelessly transmits the information to a portable computerdevice, such as a laptop, smart cell phone, personal digital assistant,or other device so that the information may be displayed thereon.

Regardless of the manner in which the patient information is displayed,or is displayable, patient support apparatus 20 is configured totransfer the patient information to another patient support apparatus 20when the corresponding patient is transferred. In this way, the patientinformation follows the patient around as he or she is moved from onepatient support apparatus 20 to another within healthcare facility 98.In the embodiment shown in FIG. 2, node 84 with first transceiver 64 andfirst transceiver controller 58 are used to control this transfer ofpatient information between support apparatuses 20, although it will beunderstood that any other transceivers could be used that enableinter-support apparatus communication.

In the example of FIG. 6, a bed 20 o is shown transferring patient datato a stretcher 20 p. More specifically, node 84 o of bed 20 o iswirelessly communicating patient information to node 84 p of stretcher20 p. This information transfer includes any of the informationmentioned above, or any other desirably transferred information. Suchinformation will typically be transferred when a patient (not shown) whowas previously supported on bed 20 o is transferred to stretcher 20 p.Once the patient and his or her corresponding patient information havebeen transferred to stretcher 20 p, stretcher 20 p may be transported toanother location, such as, for example, a room labeled “Room 2, Unit B”in FIG. 6. At the second location, the patient may, in some cases, betransferred to yet another patient support apparatus 20. In the exampleof FIG. 6, the patient may be transferred off of stretcher 20 p and ontoa different bed 20 q. When this patient transfer occurs, the stretcher20 p will also transfer the corresponding patient data to bed 20 q aswell. In this manner, bed 20 q will be in possession of the informationthat corresponds to the patient that has just been transferred thereto.Such apparatus-to-apparatus 20 transfers enable patient information tobe portable and to easily accompany a patient as he or she is movedthroughout a healthcare facility.

In some embodiments, the transfer of patient information from a firstpatient support apparatus 20 to a nearby second patient supportapparatus 20 is commenced in response to an authorized individual, suchas a caregiver, physically activating a data transfer mechanism on oneor both of the patient support apparatuses. The mechanism is implementedas a touchscreen in one embodiment, although it will be understood thatit may alternatively include one or more buttons, additionaltouchscreens, one or more switches, levers, or other physicalcomponents. Such mechanisms may be part of any of any of the usercontrols on patient support apparatus, or it may be positionedelsewhere. In the example of FIG. 2, patient support apparatus 20includes a first set of user controls 104 a located on a first siderail,a second set of user controls 104 b located on a second siderail, and athird set of user controls 104 c located on a footboard of patientsupport apparatus 20. The mechanism for transferring data betweensupport apparatuses 20 is positioned the third set of user controls 104c, although it could be positioned on any one or more of these usercontrols 104.

In some embodiments, the transfer of patient data is automaticallycommenced when patient support apparatus 20 senses that a patient hasexited and when another patient support apparatus 20 is detected to bewithin close communication distance (such as via a measurement of signalstrength between nodes 84). The detection of a patient exiting a supportapparatus 20 may be implemented by a conventional bed exit detectionsystem 106, such as, but not limited to, one of the type illustrated inFIG. 2, which includes a plurality of load cells 108 that feed forcedata into a scale system controller 52. The force data measurementsrepresent the forces exerted by the patient onto the patient supportdeck 30, and their absence and/or diminishment beyond a thresholdindicate that the patient is off of deck 30.

A patient support apparatus 20 may also be configured to receive patientinformation from another support apparatus 20, or from another source,upon the manipulation of one or more user controls 104, or it may takeplace automatically. When configured to take place automatically, thenode 84 of the receiving support apparatus 20 monitors its bed exitdetection system, or scale system, to determine if there have been anyrecent increases in weight (signifying the addition of a patient to apreviously unoccupied patient support deck 30). If there have, and ifnode 84 of the receiving support apparatus is detecting a nearby node 84that is transferring patient data, the node 84 of the receiving supportapparatus 20 stores the incoming patient data and accepts it ascorresponding to the recently added patient. If the receiving patientsupport apparatus has patient data stored therein from a prior patient,this may be automatically overwritten by the new data, or the old datamay be stored therein for future user or future retrieval.

A verification process is incorporated into the patient data transfersuch that a caregiver may easily determine whether the patient data hasbeen transferred correctly. In some embodiments, a graphic or textualdisplay on the receiving support apparatus 20 will display the receivedname of the patient and prompt the caregiver to confirm that thiscorresponds to the patient now positioned thereon. If it does not, thenthe support apparatus 20 discards or ignores the new patient data, orotherwise concludes that it does not correspond to the patient currentlyoccupying that patient support apparatus. Once the data has beenverified by the caregiver as having been properly transferred, thereceiving support apparatus 20 sends a signal back to the transmittingapparatus indicating it is OK to purge, overwrite, or no longer save,the patient data that it just transferred. In this way, the now emptypatient support apparatus will have its memory effectively empty so thatit is able to receive patient data corresponding to the next patient. Insome embodiments, a patient support apparatus 20 may retain the patientdata after transferring it to another support apparatus so that it maybe retrieved for potential further use.

In addition to patient data, the transferred data may also includeinformation about the usage of patient support apparatus, such as theamount of time the patient support apparatus was used by a particularpatient, and/or any other information that may be useful for billingpurposes. Still further, as will be described in greater detail below,the transferred information may include information gathered by one ormore medical devices that were used or associated with the patient,including not only medical information that may be useful for treatingor caring for the patient, but also usage information that may be usefulfor billing purposes.

The automatic transfer of information to an adjacent patient supportapparatus may also be configured to be implemented based upon an radiofrequency (RF) tag, bracelet, or other structure worn by a patient thatmay be detected automatically by one or more sensors positioned on eachof the patient support apparatuses. When a support apparatus 20 detectsa new patient has entered it via such a tag, bracelet, or other device,it requests via one or more node 84 transmissions that the adjacentpatient support apparatus transfer the corresponding patientinformation, or other information, to it.

FIG. 7 illustrates yet another use for nodes 84 in one or more patientsupport apparatuses. Specifically, FIG. 7 illustrates how nodes 84 areuseful for communicating medical information received from one or moremedical devices 110. The use of nodes 84 in patient support apparatuses20 to communicate medical information may be the sole use of nodes 84 ina given patient support apparatus, or it may be combined with any of theaforementioned use of nodes 84 in patient support apparatuses 20 (e.g.mesh network communication, location determination, and patientinformation storage and transfer).

In the arbitrary example illustrated in FIG. 7, a patient 112 is shownpositioned on a bed 20 r having associated therewith two medical devices110 a and 110 b. Medical devices 110 a and 110 b are configured tocommunicate with node 84 r of bed 20 r. Medical devices 110 a and 110 btherefore are able to transfer data gathered by the medical devices 110a and 110 b to bed 20 r, which either uses some or all of thetransferred information itself, or it forwards it on for communicationto healthcare network 70. Patient support apparatus 20 s similarly hastwo medical devices 110 associated with it—devices 110 c and 110 d—whichcommunicate information to node 84 s on bed 20 s. A third bed 20 t isshown with no medical devices associated with it, yet it may still be incommunication via its associated node 84 t with node 84 r and/or node 84s.

As was alluded to above, each patient support apparatus 20 in someembodiments includes a sensor for automatically detecting a patient IDdevice 114 that is worn, or otherwise carried with, each patient. Thepatient ID device 114 carries sufficient information for one or moresensors on patient support apparatus 20 to automatically determine theidentity of a patient positioned thereon. With this patient information,support apparatus 20 is able to associate the data received from the oneor more medical devices 110 that are communicating data to supportapparatus 20 so that the medical data is correlated to a specificpatient. The patient support apparatus 20 then forwards this medicaldata, with the corresponding patient identification, to network 70,which includes one or more applications or servers that utilize thisdata. Such servers or applications may include an electronic medicalrecords system, or other system.

When forwarding this data to network 70, the nodes 84 of the respectivesupport apparatuses 20 may forward the information thereto by firsttransmitting the information to one or more intermediate patient supportapparatuses before the data ultimately arrives at network 70. This mayinvolve routing the data through a mesh network, as describedpreviously, or it may be forwarded in other manners. As shown in FIG. 7,beds 20 s and 20 t both forward data to access point 68, and receivedata from access point 68, by routing the data through bed 20 r. Bed 20r, on the other hand, may communicate directly with access point 68 viasecond transceiver 66.

FIG. 9 illustrates an alternative electrical control system 144 that maybe used on any one or more of the patient support apparatuses 20described herein. Electrical control system 144 includes multiplecomponents that are common to electrical control system 44 describedabove (FIG. 2). Those components in common are labeled with the samereference numbers, and operate in the same manners described above.Further description of those components is therefore not provided.

Electrical control system 144 differs from the previously describedcontrol system 44 in that first and second transceivers 64 and 66,respectively, have been eliminated. A local transceiver 116 has alsobeen added, along with a local transceiver controller 118. Localtransceiver 116 is adapted to communicate with a detachable computer 120that is physically supportable on patient support apparatus 20. Morespecifically, local transceiver 116 communicates via Bluetooth, ZigBee,or any other suitable wireless protocol with a computer transceiver 122incorporated into detachable computer 120. Detachable computer 120 is aconventional a laptop, a tablet computer (such as, but not limited to,an iPad), or any other portable computer that may be removably coupledto patient support apparatus 20. The removable coupling of the computer120 to patient support apparatus 20 may involve only a physical couplingin which the computer is physically supported and/or secured to patientsupport apparatus 20, but communication takes place wirelessly.Alternatively, the coupling may involve one or more wires, such ascommunication wires, that are connected between the computer 120 andpatient support apparatus 20. In either case, the computer 120 is ableto communicate with transceiver 116 such that information may be sentfrom computer 120 to patient support apparatus 20, and/or informationmay be received from patient support apparatus 20 by computer 120. Suchinformation includes any of the information discussed above in any ofthe embodiments described herein such as, but not including, patientinformation, medical information, bed status information, relayedinformation received from other support apparatuses 20, information tobe relayed to other patient support apparatuses 20, locationinformation, etc.

The coupling of computer 120 to patient support apparatus, in someembodiments, enables the computer 120 to function as a user interface inwhich any or all functions of the patient support apparatus 20 are ableto be controlled by computer 120. In one embodiment, when computer 120is coupled to patient support apparatus 20, a touch screen on computer120 appears that includes icons and/or graphics that mimic a controlpanel already on patient support apparatus 20, or that mimics a controlpanel that is of the type that might be on patient support apparatus 20,thereby giving the caregiver the means for controlling patient supportapparatus 20 through computer 120. One example of a removable computerthat may be coupled to a patient support apparatus 20 is described ingreater detail in commonly assigned, copending U.S. provisional patentapplication Ser. No. 13/783,699, filed Mar. 4, 2013 by applicants CoryHerbst et al. and entitled PATIENT SUPPORT, the complete disclosure ofwhich is hereby incorporated herein by reference. Any or all of theother features described in this application may also be incorporatedinto any of the patient support apparatuses 20 described herein.

FIG. 10 illustrates an arbitrary portion of a healthcare facility 98 inwhich multiple patient support apparatuses 20 are shown incorporatingmultiple of the concepts described herein. These include the use ofnodes 84 for determining location, for creating a mesh network, fortransferring patient information, and for relaying medical deviceinformation. For example, patient support apparatus 20 c receivesinformation from medical devices D1 and D2, which it then relays ontopatient support apparatus 20 a via direct communication between nodes 84c and 84 a. When patient support apparatus 20 a receives thisinformation, it passes it onto network 70 via transceiver 66.Alternatively, if the connection between patient support apparatus 20 aand network 70 is not operable, or otherwise not suitable, patientsupport apparatus 20 a is able to relay this information to anothersupport apparatus 20 that then forwards this information to network 70.

Also shown in FIG. 10 is the transfer of patient information fromsupport apparatus 20 a to support apparatus 20 z, which then moves downone or more hallways to a different room, where it then transfers to thepatient information to support apparatus 20 b. This patient informationis transferred via nodes 84 in any of the manners described above. Whilestretcher 20 z is in transit, it may determine its location using nodes84 by any of the triangulation, trilateration, or mutlilaterationmethods described herein, or in other manners. Any information on any ofthe servers or applications on network 70 may also be transmitted to thedesired patient support apparatus in a reverse manner.

It will be understood by those skilled in the art that the use of theterm “transceiver” throughout this specification is not intended to belimited to devices in which a transmitter and receiver are necessarilywithin the same housing, or share some circuitry. Instead, the term“transceiver” is used broadly herein to refer to both structures inwhich circuitry is shared between the transmitter and receiver, andtransmitter-receivers in which the transmitter and receiver do not sharecircuitry and/or a common housing. Thus, the term “transceiver” refersto any device having a transmitter component and a receiver component,regardless of whether the two components are a common entity, separateentities, or have some overlap in their structures.

A location detection system for a facility is generally shown at 220 inFIG. 11. The location detection system 220 is described as beingintegrated into a patient handling device 222 of a healthcare facilitysuch as a hospital. Patient handling devices 222 include devices such asbeds, stretchers, cots, wheelchairs, and the like. It should beappreciated that the concepts provided by the present invention couldalso be applied to other devices located in a healthcare facilityincluding, but not limited to infusion pumps, patient monitoringdevices, patient therapy devices such as stand-alone therapy mattresses,and the like. It should also be appreciated that these principles couldbe applied to non-healthcare facilities. For purposes of description,reference is generally made to healthcare facilities.

Referring to FIG. 11, the healthcare facility includes several systemsthat can be placed in electronic communication with one another througha common network 232. These systems include admission-discharge-transfer(ADT) systems 224 and patient throughput systems 226 such as thoseoffered by Premise Development Corporation. These systems may alsoinclude eICU systems 228 such as those provided by Cerner Corporationfor the remote monitoring of critically ill patients. A nurse callsystem 230 may also be in communication with the network 232. Forinstance, a nurse call system provided by Rauland-Borg Corporation canbe used to instantly transfer nurse calls from a patient to the network232, or to the patient's primary and/or secondary caregivers via awireless phone 233 using well-known messaging interfaces 235. Thisplaces the patient in immediate contact with a healthcare professionalto provide faster, more efficient service.

Several communication devices may also be used to access the data orinformation provided by these systems 224, 226, 228, 230 to receivemessages or alerts from these systems 224, 226, 228, 230, or to transmitinformation to these systems 224, 226, 228, 230. For instance, awireless badge 246 may be in communication with these systems 224, 226,228, 230 via wireless access points 236 provided throughout thehealthcare facility. Healthcare professionals, e.g., nurses, nurse'saides, medical assistants, nurse practitioners, physician assistants,physicians, etc., may carry the wireless badges 246 to alert the nursewhen a patient has called for assistance, or that an alarm condition ispresent. The nurse could also use the wireless badge 246 to speak to avoice recognition system to report an alarm condition, or to report thatthe nurse has completed a task, to report any event that may occur inthe healthcare facility. Personal digital assistants (PDAs) 238 couldalso be in communication with the networked systems 224, 226, 228, 230to transfer data and information between the PDAs 238 and the network232. Similarly, laptop computers 240 could be used to transfer data andinformation.

Asset tracking systems 242 may also be integrated into the network 232.Such systems 242 may include those offered by Radianse, Inc., VersusTechnology, Inc. or others to track assets throughout the healthcarefacility. In some embodiments, the location detection system 2220 isintended to operate independently of the asset tracking system 242 tospecifically identify the location, e.g., room and zone, of the patienthandling devices 222. In other embodiments, the location detectionsystem 2220 of the present invention is intended to work in conjunctionwith the asset tracking system 242 to identify the location of thepatient handling devices 222 in the healthcare facility.

Still referring to FIG. 11, in one embodiment of the present invention,the patient handling device 222 is adapted for communicating with thenetwork 232. More specifically, a central processing unit 244 (CPU) ofthe patient handling device 222 is in electronic communication with thenetwork 232 via a communication module 248. The CPU 244 carries out thefunctions of the patient handling device 222 such as motor functions forraising or lowering movable sections of the patient handling device 222in response to user input, sensing functions for sensing siderailpositions, bed height, patient position or bed exit, patient weight,brake positions, and the like, as will be appreciated by those skilledin the art, or therapy functions for a therapy mattress, such asrotation, percussion, or vibration functions. The CPU 244 includes thenecessary processors and memory for carrying out these functions as willbe appreciated by those skilled in the art.

The CPU 244 and communication module 248 are physically supported by thepatient handling device 222 to move with the patient handling device 222from location to location. Preferably, one or more housings enclose theCPU 244 and the communication module 248 with the housing or housingsbeing mounted to a frame of the patient handling device 222. As aresult, all of the hardware necessary for connecting the CPU 244 of thepatient handling device 222 to the communication module 248 is locatedon and supported by the patient handling device 222. It should beappreciated that the CPU 244 and the communication module 248 could beintegrated into a single chassis or could be separate connectablecomponents linked together in a wired or wireless configuration. Byproviding the communication module 248 on the patient handling device222, the patient handling device 222 acts as a communication center orlink for transmitting data and/or information related to the patienthandling device 222, including its location, to the network 232.

The communication module 248 may be connected to the network 232 via awired and/or wireless connection to transfer data and/or informationback and forth between the CPU 244 and the hospital network 232. In awired configuration, the communication module 248 may be a transceiverwired through a communication link 49 to the hospital network 232. Thecommunication link may be an RS-232 cable, and Ethernet-compliant cable,or any other wired connection known to those skilled in the art. In awireless configuration, the communication module 248 may be a wirelesstransceiver or router that is configured with a compatible wirelesstransceiver or router 251 located on the hospital network 232. In someembodiments, both wired and wireless configurations are present on thepatient handling device 222 to easily accommodate user preferences. Itshould be appreciated that in some patient handling devices 222, thereis no CPU 244, but instead a plurality of electronic modules thatcommunicate on a peer-to-peer network. In this instance, thecommunication module 248 is simply one of the modules or nodes in thepeer-to-peer network. However, for purposes of description, reference ismade to a master/slave system utilizing the CPU 244 of the patienthandling device 222.

A processing station 250 is in communication with the network 232 toprocess data and/or information received from the various systems 224,226, 228, 230, 242 or the patient handling device 222 via thecommunication module 248 to configure or control the various systems224, 226, 228, 230, 242 or the patient handling device 222. In oneembodiment, the processing station 250 is positioned at a centralnurse's station in the healthcare facility and is implemented in aworkstation, e.g., a personal computer, for use at the central nursestation. The workstation may include software configured to manipulatedata and/or information received from the various systems 224, 226, 228,230, 242 or the patient handling device 222. For instance, theworkstation may be configured to receive data and/or information fromthe communication module 248 of the patient handling device 222 or totransfer data and/or information back to the patient handling device222. Such data may originate from a bed exit detection system, a bedheight detection system, a weight scale, a siderail sensing system thatdetects a position of the siderails, a therapy mattress, and the like.The processing station 250 preferably includes a graphical userinterface on a touch-screen display for reviewing and manipulating thedata and/or information. It should be appreciated that the processingstation 250 may also be a stand-alone unit that is not located on thenetwork 232, but includes the necessary hardware to link to thecommunication module 248 of the patient handling device 222.

Referring to FIG. 12, a typical room floor plan in a healthcare facilityis illustrated. As shown, the room, labeled Room 1, includes two zones,labeled Zone A and Zone B. These zones A, B are also often referred toas bed bays or bed areas. The location detection system 220 of thepresent invention is configured to determine the particular zone inwhich the patient handling device 222 is located. In the embodiment ofFIG. 12, two patient handling devices 222 are illustrated forpositioning at a location, e.g., Zone A and Zone B, in the healthcarefacility. The location detection system 220 shall only be described withreference to one of the patient handling devices 222. Of course, itshould be appreciated that the location detection system 220 is utilizedto determine the specific locations of several patient handling devices222 simultaneously throughout the health care facility. Multiple patienthandling devices 222 may also be located in the same zone A, B.

Referring to the patient handling device 222 shown in Zone A of the roomfloor plan of FIG. 12, a locator 252 is fixed relative to the patienthandling device 222. The locator 252 is affixed to a wall of the room, afloor of the room, or a ceiling of the room. The locator 252 may also besuspended from any location in the room such as by a tether or any otherrestraining mechanisms or devices adapted to maintain the locator 252 ina fixed relationship relative to the patient handling device 222. Inother words, in the embodiment of FIG. 12, the locator 252 is notdesigned to be mobile for transport outside of the room. The locator 252is programmed with a unique location identifier that corresponds to thelocation of the patient handling device 222. The unique locationidentifier may simply be a serial number of the locator 252 that isentered into a look-up table stored in accessible memory of theprocessing station 250 and associated with the zone in which the locator252 is installed.

The processing station 250, which is remotely located relative to thepatient handling device 222 and the locator 252, receives the uniquelocation identifier such that the location of the patient handlingdevice 222 can be determined and monitored remotely from the patienthandling device 222. More specifically, a receiver 254 is supported bythe patient handling device 222 and receives the unique locationidentifier corresponding to the location, and the communication module248, which is electronically coupled to the receiver 254, transmits theunique location identifier of the locator 252 from the patient handlingdevice 222 to the processing station 250. As a result, the patienthandling device 222 acts as a communication link between the locator 252and the processing station 250. About the same time, the communicationmodule 248 transmits or communicates a unique ID of the patient handlingdevice 222 to the processing station 250 such that the processingstation 250 can correlate the location of the patient handling device222 with the unique ID of the patient handling device 222.

A separate look-up table is utilized by the processing station 250 tocorrelate the unique ID to a patient for which the specific patienthandling device 222 is associated. The processing station 250 thencorrelates the unique ID and patient to the particular zone in which thespecific patient handling device 222 is now located such that thesoftware application installed on the processing station 250 canaccurately manage data corresponding to the specific patient handlingdevice 222 and the patient.

In one embodiment, the locator 252 includes at least one infraredtransmitter 256 for transmitting the unique location identifier to thereceiver 254 and the receiver 254 includes a housing supporting at leastone infrared sensor 258 for receiving the unique location identifierfrom the infrared transmitter 256. In this instance, transmitting theunique location identifier from the locator 252 to the patient handlingdevice 222 is further defined as transmitting an infrared locationsignal from the at least one infrared transmitter 256 of the locator 252to the at least one infrared sensor 258 of the receiver 254. Thoseskilled in the art appreciate that other data, besides the uniquelocation identification may also be transmitted from the infraredtransmitter 256, e.g., battery strength of a battery 260 in the locator252, time/date, etc.

The receiver 254 is configured to include at least one infraredtransmitter 256 for transmitting a request signal to the locator 252.Likewise, the locator 252 is configured to include at least one infraredsensor 258 to receive the request signal from the receiver 254. Thebattery 260, rechargeable or otherwise, is used to power the locator252. To conserve battery life, the locator 252 normally operates in asleep mode until the request signal is received by the at least oneinfrared sensor 258 of the locator 252.

Referring to the electrical schematic of FIG. 13, one embodiment of thelocator 252 is shown in more detail. In this embodiment, the locator 252includes a plurality of infrared transmitters 256 for transmitting theunique location identifier to the receiver 254. Likewise, the locator252 includes a plurality of infrared sensors 258 arranged in a sensorarray 262 for receiving the request signal from the receiver 254. Thelocator 252 also includes a microprocessor 264 electrically coupled tothe sensor array 262 and the infrared transmitters 256. Themicroprocessor 264 is pre-programmed with the unique location identifierthat corresponds to the location of the patient handling device 222 andcontrols the infrared transmitters 256 to produce a signal with theunique location identifier and transmit the signal to the receiver 254of the patient handling device 222. The infrared transmitters 256 of thelocator 252 are adapted to provide variable power transmission tominimize cross talk and maximize signal integrity. The locator 252 isalso adapted to modulate light intensity from the infrared transmitters256 to maximize noise immunity. Finally, a filter (not shown) may beused to filter the infrared signal to reduce receiver saturation andmaximize signal integrity and noise immunity.

Referring to the electrical schematic of FIG. 14, one embodiment of thereceiver 254 of the patient handling device 222 is shown in more detail.In this embodiment, the receiver 254 includes a plurality of infraredsensors 258 arranged in a sensor array 262 for receiving the uniquelocation identifier from the infrared transmitters 256 thereby improvingtransmission of the unique location identifier. Likewise, the receiver254 includes a plurality of infrared transmitters 256 for transmittingthe request signal from the receiver 254 to the locator 252 therebyimproving transmission of the request signal. The receiver 254 may alsobe battery powered, but is preferably powered by an AC power source usedto power a control system and the CPU 244 of the patient handling device222. Those skilled in the art realize that the locator 252 and receiver254 may each be implemented with a single infrared transmitter 256 andinfrared sensor 258.

Referring to FIG. 15, a process flow diagram illustrates a method ofdetecting the location of the patient handling device 222. Initially,the locator 252 is in the sleep mode and awaits the request signal fromthe receiver 254. In other words, the microprocessor 264 looks on areception channel to see if the patient handling device 222 hasrequested location information, e.g., the unique location identifier. Ifthe patient handling device 222 has not requested the unique locationidentifier, the locator 252 remains in the sleep mode. If the patienthandling device 222 sends the request signal and the request signal isproperly received and understood by the locator 252, then the locationsignal sends the location information, i.e., the unique locationidentifier on a transmission channel. Once the unique locationidentifier is sent, the locator 252 returns to the sleep mode toconserve battery life.

Referring to FIG. 16, a process flow diagram illustrates a method ofsending the request signal to the locator 252 from the receiver 254. Thereceiver 254, which is preferably powered by an AC power source,regularly transmits the request signal to continually update thelocation of the patient handling device 222. The timing of thesetransmissions can differ depending on whether or not the receiver 254has recently received the location information or not. As a result,there may be multiple predetermined delays between request signals,e.g., delay #1 and delay #2, which differ in the amount of time betweentransmissions of the request signal to the locator 252 on a transmissionchannel of the receiver 254. Once the location information is received,the information is processed and the unique location identifier is senton to the CPU 244 and ultimately the processing station 250 to determinethe location of the patient handling device 222.

Referring to FIG. 17, alternative location detection systems are shownwith similar features to that of the previously described embodiment. InFIG. 17, the locator 252 may be one of: a radio frequency identification(RFID) tag 276 for transmitting the unique location identifier usingradio frequency; an ultrasonic transmitter 280 for transmitting theunique location identifier using ultrasonic signals; an inductivelycoupled transmitter 284 for transmitting the unique location identifierusing principles of magnetic inductive coupling; or a modulated lighttransmitter 288 for transmitting the unique location identifier usingmodulated light. It should be appreciated that in each of theseembodiments, the receiver 254 is particularly adapted for receiving thespecific signal types mentioned, i.e., the receiver 254 may be a RFIDreader 278, or include an ultrasonic sensor 282, an inductively coupledsensor 286, or a modulated light sensor 290.

Referring to FIGS. 18-21, further alternative systems using RFID areshown. It should be appreciated that any of the systems using RFID couldbe active, semi-active, or passive RFID systems as is well known tothose skilled in the art. In general, when a passive system is employed,each of the tags 276 described contains a transponder (not shown) with adigital memory chip (not shown) that is given or programmed with theunique location identifier. An interrogator (not shown), which is anantenna packaged with a transceiver and decoder in the RFID reader 278emits a signal activating the RFID tags 276 so that the interrogator canread and write data to the RFID tags 276. When the patient handlingdevice 222 is moved into the particular zone in the room, the RFID tags276 detect the RFID reader's activation signal. The RFID reader 278 thendecodes the data, e.g., the unique location identifier, encoded in theRFID tag's digital memory chip and the data is passed to the processingstation 250 as previously described.

In the embodiment of FIG. 18, the locator 252 comprises an RFID tag mat292 that includes an array of RFID tags 276. At least one of the tags276 transmits the unique location identifier, or a selected set of theRFID tags 276 transmits a signal that is recognized as the uniquelocation identifier. In this embodiment, the receiver 254 is an RFIDreader 278 for receiving the signals from the RFID tags 276. In use, thehealthcare professional or other employee of the healthcare facilitywould first move the patient handling device 222 into position eitherover the RFID tag mat 292 or in close proximity to the RFID tag mat 292.The RFID tags 276, or at least a portion thereof, would then transmitthe unique location identifier to the RFID reader 278, which would thentransmit the unique location identifier to the CPU 244 and then to theprocessing station 250 located on the network 232 via the communicationmodule 248, as previously described.

In the embodiment of FIG. 19, the locator 252 comprises an RFID swipecard 294 having at least one active or passive RFID tag 276. The RFIDswipe card 294 is tethered to a head wall 324 of the room using a tether268. This fixes the RFID swipe card 294 in the room relative to thepatient handling device 222. The receiver 254 is an RFID reader 278 thatreceives the unique location identifier from the RFID tag 276 embeddedin the RFID swipe card 294. In this embodiment, a healthcareprofessional would first move the patient handling device 222 intoposition in the particular zone in the room and then swipe the RFIDswipe card 294 over the RFID reader 278 to transfer the unique locationidentifier from the RFID tag 276 to the RFID reader 278 and on to theprocessing station 250.

In the embodiment of FIG. 20, the locator 252 comprises a magnetic RFIDtag 270. The magnetic RFID tag 270 is tethered to the head wall 324 asin FIG. 19, using a tether 268. However, in this embodiment, thehealthcare professional or other employee of the healthcare facilitydoes not merely swipe the magnetic RFID tag 270 to transmit the uniquelocation identifier to the RFID reader 278. Instead, the RFID reader 278magnetically attracts the magnetic RFID tag 270 to releasably lock themagnetic RFID tag 270 to the RFID reader 278 to ensure a completetransmission of the unique location identifier to the processing station250 in the manner described above.

In the embodiment of FIG. 21, the locator 252 comprises an RFID tag 276and the receiver 254 comprises an RFID reader 278 similar to FIGS.18-20. However, this embodiment further includes a cable 272 that wouldbe maintained at each zone A, B. The cable 272 interconnects a nursecall interface of the patient handling device 222 to a standard nursecall interface port 274 located at each zone A, B. The RFID reader 278is integrated into the nurse call interface located on the patienthandling device 222 and the RFID tag 276 is integrated into an end ofthe cable 272 such that when the cable 272 connects the nurse callinterface on the patient handling device to the nurse call interfaceport 274 mounted to the head wall 324, the RFID tag 276 would transmitthe location information, e.g., unique location identifier, to the RFIDreader 278 and on to the processing station 250 located on the network232.

Referring to FIGS. 22-25, further alternative systems are shown. In theembodiment of FIG. 22, the locator 252 comprises a plurality of WiFiaccess points 296 located throughout the room and programmed with uniquelocation identifiers for the zones in the room in which they arelocated. This system is capable of triangulating the room and zonelocation of the patient handling device 222 using the WiFi access points296. The receiver 254 further comprises a WiFi transceiver 95 mounted tothe patient handling device 222. The WiFi transceiver is incommunication with the WiFi access points 296 to receive referencesignals transmitted by the WiFi access points 296. In some embodiments,the strength of the signal received in combination with the uniquelocation identifiers programmed into the WiFi access points 296 could beused to triangulate the room and zone location of the patient handlingdevice 222. The WiFi transceiver 95 communicates the locationinformation to the processing station 250 located on the network 232.

In the embodiment of FIG. 23, the locator 252 comprises an IDtransmitter 298 integrated into a 110 Volt AC plug 300 that transmits areference signal to the receiver 254 located on the patient handlingdevice 222. In this embodiment, the receiver 254 is integrated into apower cord interface 301 to communicate with the ID transmitter 298through a power cord 303. The receiver 254 would then communicate thelocation information, e.g., unique location identifier, to theprocessing station 250 located on the network 232.

In the embodiment of FIG. 24, the locator 252 comprises an Ethernet port302 and the receiver 254 comprises an Ethernet transceiver 304 mountedto the patient handling device 222. An Ethernet-compliant cable 306interconnects the Ethernet transceiver 304 and the Ethernet Port 302 tosend location information to the patient handling device 222. TheEthernet transceiver 304 then communicates the location information tothe processing station 250.

In the embodiment of FIG. 25, the system utilizes a mesh network 308with mesh network transceivers 310 to determine the locationinformation. The mesh network 308 may be wired or wireless, preferablywireless to reduce infrastructure costs. The wireless mesh network 308allows mesh network transceivers 310 to transmit data through oneanother onto the network 232 and the processing station 250. In otherwords, in the wireless mesh network 308, access points and wirelessdevices can organize themselves into an ad hoc network, communicatingwith each other to determine the fastest way to send data to the network232. In the wireless mesh network 308, data hops from mesh networktransceiver 310 to mesh network transceiver 310 looking for the shortestavailable path to the network 232 and the processing station 250. Here,each of the patient handling devices 222 is equipped with a mesh networktransceiver 310, which acts as a node on the mesh network 308. Thelocation information is obtained by knowing the association of the meshnetwork transceivers 310 on the patient handling devices 222 relative tothe other mesh network transceivers 310 and/or a base transceiver (notshown). For instance, adjacent patient handling devices 222 in a secondzone of the room, e.g., Zone B of Room 1, could determine the locationinformation using the mesh network transceiver 310 on the patienthandling device 222 in Zone A of Room 1.

Referring to FIGS. 26-29, alternative location detection systems areshown for determining the location in which the patient handling device222 is located by separately determining first and second areas of thelocation. In one embodiment, the first area is the room, e.g., Room 1,in which the patient handling device 222 is located, and the second,subarea, is the zone in the room in which the patient handling device222 is located, e.g., zones A, B. One of the previously describedlocation detection systems may be used to determine the first area inwhich the patient handling device 222 is located. In this instance, thepreviously described systems would be enabled to only provide first areaor room locations and not specific zone locations. In other words, thepreviously described systems would provide a first locating device,e.g., locator 252, mesh network transceiver 254, etc., associated withthe patient handling device 222 and in communication with the processingstation 250 to transmit a first unique location identifier to theprocessing station 250. The first unique location identifier beingassociated with the first area in which the patient handling device 222is located, but not the subarea or particular zone in which the patienthandling device 222 is located.

The asset tracking system 242 of the healthcare facility could also bethe first locating device used for this purpose. In this instance, eachof the patient handling devices 222 would be equipped with an asset tag314 for tracking the patient handling devices 222 in the healthcarefacility with the asset tracking system 242 being adapted to provideroom locations for the patient handling devices 222 and transmit thoseroom locations to an asset tag receiver 316 on the network 232, and onto the processing station 250. For purposes of description, reference ismade to the first locating device being the asset tracking system 242.

The alternative location detection systems of FIGS. 26-29 provide asecond locating device 109 associated with the patient handling device222 and in electronic communication with the processing station 250 totransmit a second unique location identifier to the processing station250. The second unique location identifier corresponds to the subarea orzone in which the patient handling device 222 is located. Thus, thefirst unique location identifier provides the general vicinity in whichthe patient handling device 222 is located, while the second uniquelocation identifier further refines the description of the location topinpoint the location of the patient handling device 222. Referringfirst to FIG. 26, the second locating device may be an electronic switch318 that can be manually actuated to correspond to the appropriate zoneA, B. The switch 318 would be in communication with the network 232 andprocessing station 250 to identify the zone A, B selected.

Referring to FIGS. 27 and 28, the second locating device 109 is a sonicdistance sensor 320 or a laser distance finder 322 used to determine thezone A, B in which the patient handling device 222 is located. In theseembodiments, the sonic distance sensors 320 or laser distance finders322 would be adapted to generally measure distances from walls 324, 325located in the first area, e.g., Room 1, to further determine theposition of the patient handling device 222 in the room. A look-up tablecould be loaded into the processing station 250 with predeterminedranges of distances provided to correspond to the different zones A, B.For instance, once the patient handling device 222 is wheeled or movedinto room, the sonic distance sensors 320 or laser distance finder 322may be manually or automatically operated to measure the distance frompredetermined boundaries, e.g., walls 324, 325, with the measureddistances being compared to the look-up table and with a correspondingzone A, B selected therefrom.

Referring to FIG. 29, the second locating device is a hall-effect sensor326 operable with a room magnet 328 or plurality of room magnets 328located in the room to determine the zone location of the patienthandling device 222. In each of the embodiments of FIGS. 26-29, thesonic distance sensors 320, laser distance finder 322, and hall-effectsensor 326 would be adapted to transmit signals that communicate, eitherdirectly or indirectly, with the processing station 250 to display theroom and zone location of the patient handling device 222. In oneversion, the communication module 248 is in electronic communicationwith these second locating devices 109 and the processing station 250 totransmit the second unique location identifier from the second locatingdevices 109 to the processing station 250. Again, as with the previouslydescribed embodiments, the patient handling device 222 has a unique IDand the communication module 248 communicates the unique ID to theprocessing station 250 such that the processing station 250 cancorrelate the first unique location identifier and the second uniquelocation identifier to the patient handling device 222 to determine theroom and zone location of the patient handling device 222.

FIG. 30 depicts another alternative location detection system 420.Location detection system 420 includes a person support apparatus 422having a base 424, a frame 426, and a support surface 428 adapted tosupport a person 430 thereon. Person support apparatus 422 also includesa controller 432 that is in communication with a wireless transceiver434. Wireless transceiver 434 communicates wirelessly with one or morewireless access points 436. Wireless access points 436 are incommunication with a local area network 438 of the healthcare facilityin which person support apparatus 422 is located. In some embodiments,local area network 438 is an Ethernet-based computer network.

Controller 432 includes one or more microprocessors, microcontrollers,field programmable gate arrays, systems on a chip, volatile ornonvolatile memory, discrete circuitry, and/or other hardware, software,or firmware that is capable of carrying out the functions describedherein, as would be known to one of ordinary skill in the art. Wirelessaccess points 436 are, in at least one embodiment, conventional WiFiaccess points (IEEE 802.11) that allow wireless devices—such as, but notlimited to, wireless transceivers 434—to connect to computer network438. Wireless transceivers 434 are, in at least one embodiment,conventional WiFi transceivers capable of communicating with network 438via access points 436.

Location detection system 420 (FIG. 30) operates to determine thelocation of person support apparatus 422 by communicating with one ormore of the wireless access points 436. Each WiFi access point 436 sendsmessages that are received by wireless transceiver 434. Wirelesstransceiver 434 includes an antenna and circuitry that is adapted todetermine a received signal strength indicator (RSSI) of at least one ofthe messages sent from the wireless access points 436 in which it is incommunication with. In an alternative embodiment, wireless transceiver434 includes circuitry that is adapted to determine a received channelpower indicator (RCPI) of at least one of the messages sent from each ofthe wireless access points 436 that it receives a message from. In stillother embodiments, wireless transceiver 434 includes circuitry that isadapted to determine both an RSSI and a RCPI of at least one of themessages sent from each of the wireless access points 436 that itreceives a message from.

Each wireless access point 436 includes within at least one of themessages that it sends to wireless transceiver 434 a media accesscontrol (MAC) address of that particular wireless access point 436.Location detection system 420 includes a map of the location of eachwireless access point 436 that is stored in an electronic memory (notshown). The map includes data indicating the location of each accesspoint 436 within the facility, as well as an identification of whichfloor each wireless access point 436 is located on in a multi-storyfacility. Each of the individual wireless access points 436, in at leastone embodiment, are identified in the map data using their respectiveMAC address. The map data therefore includes a location within thefacility for each of the MAC addresses of the wireless access points436.

In one embodiment, the map data is stored in a memory that is on-boardperson support apparatus 422 and electronically accessible to controller432. In this embodiment, person support apparatus 422 determines anestimate of its location within the facility based upon this map dataand the signal strength data (RSSI and/or RCPI) of the messages itreceives from wireless access points 436. In another embodiment, the mapdata is stored on a server, or other device (e.g. processing station 250of FIG. 11), that is on computer network 438. In such an embodiment, theserver or other network device determines an estimate of the location ofperson support apparatus 422 based upon this map data and the signalstrength data (RSSI and/or RCPI). After determining the locationestimate of the person support apparatus 422, the server or othernetwork device—in some embodiments—transmits a message to thatparticular person support apparatus 422 that identifies the currentlocation of person support apparatus 422. As will be discussed ingreater detail below, once person support apparatus 422 knows itslocation, either from determining it itself or receiving it from aserver or other network device, person support apparatus 422 thencommunicates this location data—in some embodiments—to other personsupport apparatuses, a nurse call system, and/or other devices.

The location estimate of person support apparatus 422, determined byeither controller 432 or a network device, is determined bytriangulating and/or trilaterating signal strength data and locationdata corresponding to multiple wireless access points 436. Wherewireless transceiver 434 is in communication with more wireless accesspoints 436 than is necessary to estimate its position, the locationestimate is enhanced by utilizing signal strength data from all of thewireless access points and a computation of a best fit of all of theavailable data, in at least some embodiments. In other embodiments, oneor more of the signal strength indicators are discarded by the processoror server when more wireless access points 436 are in communication withtransceiver 434 than are necessary to determine the location of personsupport apparatus 422.

The number of wireless access points 436 that person support apparatus422 must be in communication with in order to determine its position mayvary, depending upon the particulars of the facility in which personsupport apparatus 422 is located. For example, if person supportapparatus 422 is triangulating or trilaterating its position in asingle-story facility based off of communication with only two wirelessaccess points 436, and the signal strength data is used a proxyindication of its distance from each of the wireless access points 436,then an initial estimate of its position may yield two differentpossible locations within the facility. However, in many situations, oneof the two different possible locations can be excluded based upon otherdata, such as map data indicating that one of the two possible locationslies outside the facility, or in an area inaccessible to the personsupport apparatus. Other data may also be used to narrow the twopossible locations down to one. In a multi-story facility, it may benecessary in least some situations, to communicate with at least threedifferent wireless access points 436 in order to determine the locationof person support apparatus 422. In other situations, fewer wirelessaccess points may be sufficient.

If controller 432 of person support apparatus 422 computes the locationestimate of person support apparatus 422, controller 432 then sends thislocation estimate, in at least one embodiment, to a device on network438, such as, but not limited to, processing station 250 (FIG. 11).Processing station 250, whether it receives the location estimate fromperson support apparatus 422 or computes the location estimate itself,then shares this location data with one or more other servers, or otherdevices, that are coupled to network 438. Such other servers that mayreceive this location data include a server of admission, discharge, andtracking system 224 (FIG. 11), a server of eICU system 228, a server ofpatient throughput system 226, and/or a server of asset tracking system242. Any of these systems may then communicate this location data tostill other devices, such as, but not limited to, laptops 240, personaldigital assistants 238, wireless badges 246, smart phones, and/or stillother devices that are in communication with network 438.

In facilities where there are multiple person support apparatuses, eachperson support apparatus 422 also sends a unique identifier to network438 that uniquely identifies that particular person support apparatus422. This identifier is used by devices on the network, such asprocessing station 250, to distinguish the multiple person supportapparatuses 422 from each other. Thus, in at least one embodiment,person support apparatus 422 sends both a unique identifier identifyingitself and signal strength data of the messages it receives fromwireless access points 436 to a network device that then uses this datato determine a location of that particular person support apparatus 422within the facility.

FIG. 31 illustrates another alternative location detection system 520.Those components of location detection system 520 that are the same ascomponents found in location detection system 420 are labeled with thesame reference number and, unless specified otherwise, operate in thesame manner as previously described.

Location detection system 520 includes, in addition to those componentsof location detection system 420, one or more short range locators 442that communicate with corresponding short range transceivers 440positioned on person support apparatus 422. One or more short rangelocators 442 are positioned at fixed and known locations within thefacility in which person support apparatus 422 is positioned. Shortrange locators 442 transmit wireless signals a relatively shortdistance, and receive wireless signals from transmitters, such astransceiver 440, when those transmitters are within a short distance oflocator 442. In some embodiments, the short range is on the order ofseveral feet. In at least one embodiment, short range locator 442transmits an infrared signal that is only received by a short rangetransceiver 440 of person support apparatus 422 if person supportapparatus 422 is oriented such that transceiver 440 has a line-of-sightpath to locator 442 and is positioned within several feet of locator442.

Person support apparatus 422 and/or a server on network 438 (e.g.processing station 250) determine a location estimate of person supportapparatus 422 using a unique identifier that is transmitted by locator442 to transceiver 440, as well as map data that identifies (by theirunique identifier) the location of each locator 442 within the facility.For example, in one embodiment, transceiver 440, upon receiving a uniqueidentifier from a specific locator 442, forwards the unique identifierto controller 432. Controller 432 consults the map data indicating thelocation of that particular locator 442 within the facility. Becauselocators 442 and transceivers 440 are only able to communicate over ashort range, controller 432 determines that the location of personsupport apparatus 422 is substantially the same as the location of theparticular locator 442 that its transceiver 440 is in communicationwith.

The granularity of the position location of person support apparatus 422that can be determined by controller 432 is not only that of individualrooms within a facility, but also of specific zones within a particularroom. Thus, for example, with reference to FIG. 12, the range ofcommunication between fixed locators 442 and transceivers 440 is limitedenough such that controller 432 is able to determine whether personsupport apparatus 422 is in zone A or in zone B. Stated alternatively,if person support apparatus 422 were positioned in zone A of FIG. 12, itwould not be able to communicate with a locator 442 positioned at thezone B location (e.g. in the position of the locator 252 that is in zoneB), and if person support apparatus 422 were positioned in zone B ofFIG. 12, it would not be able to communicate with a locator 442positioned at the zone A location.

In other embodiments, the location of person support apparatus 422 inlocation detection system 520 is determined by a device on network 438,such as processing station 250, rather than person support apparatus422. In such embodiments, controller 432 forwards the unique identifierreceived from locator 442 to the network device via transceiver 434. Thenetwork device has access to the map data indicating the locations ofeach locator 442 and uses this map data and the unique identifier sentby person support apparatus 422 to determine the location of personsupport apparatus 422. In some embodiments, processing station 250 sendsthis location data back to person support apparatus 422 viacommunication between a network access point 436 and transceiver 434.Person support apparatus 422, in some embodiments, communicates thislocation estimate to other devices, including other person supportapparatuses 422, a nurse call system, and/or other devices. Theprocessing station 250, or other device on the network that determinesthe location estimate of person support apparatus 422, may also forwardthis location estimate to other devices on the network 438 in any of themanners described above with respect to location detection system 420.

In facilities where there are multiple person support apparatuses, eachperson support apparatus 422 also sends a unique identifier to network438 that uniquely identifies that particular person support apparatus422. This identifier is used by devices on the network, such asprocessing station 250, to distinguish the multiple person supportapparatuses 422 from each other. Thus, in at least one embodiment,person support apparatus 422 sends both a unique identifiercorresponding to a particular locator 442 and a unique identifiercorresponding to itself to a network device that then uses these twoidentifiers to determine a location of that particular person supportapparatus 422 within the facility.

In at least one embodiment of location detection system 520, locators442 and transceivers 440 are the same, and operate in the same manners,as has been previously described with respect to locators 252 andreceivers 254, respectively, of FIG. 12.

Location detection system 520 also includes wireless transceiver 434which is in communication with one or more wireless access points 436.Location detection system 520 is also configured to utilize signalstrength data from the messages wireless transceiver 434 receives fromwireless access points 436 to enable a second estimate to be made of thelocation of person support apparatus 422 within the facility. That is,location detection system 520 determines an estimate of person supportapparatus 422's location in any of the same manners that have beenpreviously described above with respect to location detection system420. Thus, location detection system 520 provides both a first locationestimate generated from locators 442 and transceivers 440, and a secondlocation estimate generated from the signal strength data of themessages received by transceiver 434 from wireless access points 436.For the first location estimate, map data indicating the location ofeach locator 442 is utilized, and for the second location estimate, mapdata indicating the location of each wireless access point 436 isutilized. Either or both of these location estimates may be determinedby controller 432 or by a device on network 438, such as processingstation 250.

In at least one embodiment, controller 432 and/or processing station 250utilize only a single one of the location estimates at a given time.More specifically, in at least one embodiment, the first locationestimate generated from locator 442 and transceiver 440 is used whileperson support apparatus 422 is stationary, while the second locationestimate generated from transceiver 434 and wireless access points 436is used while person support apparatus 422 is mobile. Such an embodimentallows the location of person support apparatuses 422 to be determinedeven when they are positioned out of range of any locators 442.

In at least one embodiment where the first estimate is used while personsupport apparatus 422 is stationary and the second estimate is usedwhile person support apparatus 422 is mobile, a brake on board theperson support apparatus 422 is used as a proxy for thestationary/mobile status of person support apparatus 422. That is, whenthe brake is off, controller 432 and/or processing station 250 presumethat person support apparatus 422 is mobile and use the first locationestimate, and when the brake is on, controller 432 and/or processingstation 250 presume that person support apparatus 422 is mobile and usethe second location estimate. Such embodiments include one or more brakesensors (not shown) that are in communication with controller 432. Thestatus of the brakes is communicated to processing station 250 fromcontroller 432, in some embodiments, via transceiver 434.

In some embodiments, the network device (e.g. processing station 250) incommunication with person support apparatus 422 sends the first locationestimate to another network device (e.g. asset tracking system 242 (FIG.11) when the brake is on, and sends the second location estimate to theother network device when the brake is off. This enables not onlyprocessing station 250 to know the location of person support apparatus422 at all times (both when it is stationary and when it is mobile), butany other device or system (e.g. systems 224, 228, 226, 242) to know thelocation of person support apparatus 422 at all times. Such othersystems may include data tables that correlate the specific identity ofperson support apparatus 422 with a particular patient 430 who isoccupying person support apparatus 422, thereby enabling the system toalso know the location of a particular patient at all times, includingtimes when the patient is being transported throughout the facility onperson support apparatus 422.

In still other embodiments, whenever person support apparatus 422 is incommunication range of a locator 442, the two location estimates arecombined together to yield a third location estimate that is acombination of the first and second location estimates. The combinedlocation estimate is a weighted or unweighted average of the twolocation estimates, in at least one embodiment. Other manners ofcombining the location estimates may also be used in other embodiments.

In some embodiments, the inclusion of dual position sensing technology(e.g. locators 442 and wireless access points 436) in location detectionsystem 520 enables the system to be installed without having to manuallycalibrate person support apparatuses 422 and/or processing station 250.That is, the inclusion of the locators 442 allows the position of personsupport apparatus 442 to be determined, as discussed above. Using thatknown position information, as well as the known location of wirelessaccess points 436, controller 432 (or processing station 250) convertsthe signal strength data of the messages received by person supportapparatus 442 into distances. The system therefore does not rely upon auser manually calibrating, or otherwise inputting a conversion factor,into the system that controller 432 uses to convert signal strengths todistances. Once the conversion factor is known, the location of personsupport apparatus 422 can be determined solely by signal strength datafrom wireless access points 436 when person support apparatus 422 is outof range of a locator 442.

FIG. 32 illustrates another alternative location detection system 620.Those components of location detection system 620 that are the same ascomponents found in location detection systems 420 and/or 520 arelabeled with the same reference numbers and, unless specified otherwise,operate in the same manner as previously described.

Location detection system 620 includes, in addition to those componentsof location detection system 520, at least one device or object 444 thatis positioned within the vicinity of person support apparatus 422 and incommunication with person support apparatus 422. Device 444 is, in someembodiments, a medical device that is used in conjunction with the careof a patient who is supported or assigned to person support apparatus422 (e.g. person 430), such as, but not limited to, a pump, aventilator, a respirator, a monitor, or the like. In other embodiments,device 444 is another person support apparatus 422. In still otherembodiments, device 444 is a powered mattress that rests on top ofperson support apparatus 422.

Regardless of the specific form of device 444, device 444 and personsupport apparatus 422 are in communication. This communication, in oneembodiment, takes place via wireless transceiver 434 of person supportapparatus 422 and a transceiver on-board device 444 (not shown) thatutilizes the same communication protocol (e.g. WiFi, ZigBee, Bluetooth,etc.). In some such embodiments, communications between person supportapparatus 422 and device 444 take place directly. In other embodiments,messages from person support apparatus 422 pass through a wirelessaccess point 436 before being forwarded to device 444, and vice versa.In still other embodiments, messages from person support apparatus 422are transmitted to wireless access point 436, from wireless access point436 to a network device (e.g. processing station 250), from the networkdevice back to the same (or a different) access point 436, and from thataccess point to device 444, and vice versa.

In still other embodiments, person support apparatus 422 includesanother transceiver (in addition to transceivers 434 and 440) that usesa different communication medium and/or protocol to communicate withdevice 444. For example, in at least one embodiment, person supportapparatus 422 includes a near field transceiver (not shown) that usesnear field communication to communicate with device 444. In oneembodiment, such near field communication utilizes any of the techniquesand/or message content disclosed in commonly assigned U.S. patentapplication Ser. No. 13/802,992 filed Mar. 14, 2013 by inventors MichaelJoseph Hayes et al. and entitled COMMUNICATION SYSTEMS FOR PATIENTSUPPORT APPARATUSES, the complete disclosure of which is herebyincorporated herein by reference. Other types of near fieldcommunication can also be used.

Regardless of the form of the communication between person supportapparatus 422 and device 444, the content of the communication includesat least one message transmitted from person support apparatus 422 todevice 444 that includes the location estimate of person supportapparatus 422. The transmitted location estimate may be the firstlocation estimate discussed above (based on locator 442), the secondlocation estimate discussed above (based on wireless access points 436),or a location estimate that is based on a combination of the two. Insome embodiments, device 444 uses this location information to determineits own location.

Either of location detection systems 420 or 520 can be modified toinclude the necessary structure and programming to enable person supportapparatus 422 to communicate with device 444. Device 444 is configured,in some embodiments, to analyze the received signal strength of one ormore messages that it receives from person support apparatus 422. Thisinformation, in combination with the location estimate of person supportapparatus 422, which is sent to device 444, allows device 444 todetermine its own location by triangulating and/or trilaterating itsposition relative to the positions of multiple person supportapparatuses 422 that it is in communication with (and from which itreceives location data). In other words, person support apparatus 422,in at least some embodiments, provides location information to otherdevices 444 in a manner similar to how wireless access points 436provide location data to person support apparatus 422. That is, device444 analyzes the signal strength data of messages from multiple personsupport apparatuses 422, along with the locations of each of the personsupport apparatuses, to determine its own location. The locations ofperson support apparatuses 422, unlike wireless access points 436, aredynamic, and device 444 therefore utilizes the location data transmittedfrom each person support apparatus 422, rather than a static map.

In some embodiments, device 444 determines its location using signalstrength data from a combination of messages from one or more wirelessaccess points 436 and one or more location messages transmitted from oneor more person support apparatuses 422. This signal strength data isanalyzed in conjunction with the current location of the person supportapparatuses 422 (transmitted to device 444 from person supportapparatuses 422) and in conjunction with map data stored on board device444 that identifies the location of each individual wireless accesspoint 436 within the facility.

In some embodiments, person support apparatuses 422 are configured suchthat they act as mobile hotspots for devices, such as device 444, tocommunicate with network 438. Device 444 utilizes signal strength dataof the messages received from the hot spot person support apparatus 422,along with the location of the person support apparatus 422, todetermine their location. Person support apparatuses that includecircuitry for acting as mobile hot spots are disclosed in more detail incommonly assigned PCT patent application number PCT/US2014/024672 filedMar. 12, 2014 by applicant Stryker Corporation and entitled PATIENTSUPPORT APPARATUS WITH REMOTE COMMUNICATIONS, the complete disclosure ofwhich is hereby incorporated herein by reference. Such person supportapparatuses can be modified to include any of the components, features,and/or functions described herein with respect person support apparatus422, patient handling devices 222, and/or patient support apparatuses20.

Any of location detection systems 420, 520, and/or 620 can also bemodified such that controller 432 is configured to determine thelocation of person support apparatus 422 partially or wholly based uponsignal strength data of messages received by person support apparatus422 from other person support apparatuses 422. In such embodiments, forexample, a first person support apparatus 422 that is in communicationwith two wireless access points 436 and one wireless transceiver 434from a second person support apparatus 422 uses the signal strength dataof the messages from access points 436, the location of wireless accesspoints 436, the signal strength data of at least one message from secondperson support apparatus 422, and the current location of the secondperson support apparatus 422 (transmitted from second person supportapparatus 422 to first person support apparatus 422) to determine itsown location within a facility.

In still other embodiments, either of location detection system 520 or620 can be modified to determine the location of wireless access points436 in addition to determining the location of person supportapparatuses 422. When so modified, person support apparatus 422 analyzesthe signal strength of messages received from a first wireless accesspoint 436 while positioned at a known location (as determined by locator442 and transceiver 440). This analysis gives person support apparatus422 information about how far away the first wireless access point 436is positioned from person support apparatus 422's location. Personsupport apparatus 422 repeats this process for additional wirelessaccess points 436 while positioned at the known location, giving personsupport apparatus 422 information about the range of the additionalwireless access points 436. All of this information is stored on boardperson support apparatus 422, along with similar data that is gatheredwhen person support apparatus 422 is moved to a different location.Using this signal strength data gathered by person support apparatus 422when positioned at multiple different locations, person supportapparatus 422 is able to triangulate and/or trilaterate the position ofone or more wireless access points 436. This location data is then addedto a map of the locations of wireless access point 436 that ismaintained on person support apparatus 422, or it is transmitted to anetwork device, such as processing station 250.

Person support apparatus 422 can also share the signal strength datathat it gathers from the wireless access points it is in communicationwith other person support apparatuses 422. In other words, in someembodiments, it is not necessary for a single person support apparatus422 to move to multiple locations that are all in communication of aparticular wireless access point 436 in order to determine the locationof that wireless access point 436. Instead, multiple different personsupport apparatuses 422 that are all currently in communication with aparticular wireless access point 436 can share with each other theircurrent locations and the signal strengths of the messages they arecurrently receiving from that particular wireless access point. Theperson support apparatuses 422, or a network device in communicationwith the person support apparatuses 422, can use this data to determinea location of that particular wireless access point 436.

By having person support apparatuses 422, or a device on the network 438that is in communication with person support apparatuses 422, determinethe location of wireless access points 436, it is not necessary tomanually perform a survey of the locations of wireless access points 436and/or to transfer that surveyed data to person support apparatuses 422(or to processing station 250). Thus, a location detection system, suchas system 520 or 620, can be initially installed in a facility withouthaving to determine the locations of wireless access points 436 (or ifthe locations are known, without having to transfer this information toperson support apparatuses 422 and/or processing station 250), and thelocations of person support apparatuses 422 can all be determinedinitially using locators 442 and transceivers 440. From the locationdata generated from using locators 442 and transceivers 440, the systemcan thereafter determine the locations of the wireless access points436. Once these locations are determined, the locations of personsupport apparatuses 422 can thereafter be determined using signalstrength data of the messages of access points 436, along with theirlocations, to determine the location of person support apparatuses 422.This location data supplements the locations determined from locators442 and transceivers 440, or, as noted previously, provides locationdata when person support apparatuses 422 are mobile, or otherwise notpositioned within communication range of a locator 442.

It will be understood that, although many of the components of locationdetection systems 420, 520, and 620 have been given reference numbersdifferent from similar components in other systems and/or person supportapparatuses described herein, such components are, in at least someembodiments, configured to function that same as, and/or include thesame components as, the components that have been previously described.Thus, for example, in some embodiments, person support apparatuses 422include the same functions and/or components as any of the personsupport apparatuses 20 or patient handling devices 222 describedpreviously. As another example, controller 432 includes the samefunctions and/or components as any one or more of the following:electrical control system 44, footboard controller 48, actuator/sensorcontroller 50, scale system controller 52, 1^(st) siderail controller54, 2^(nd) siderail controller 56, 1^(st) transceiver controller 58,2^(nd) transceiver controller 60, mattress controller 62, and/or centralprocessing unit 244. Still further, network 438, in some embodiments,includes the same components and/or functions as network 70 and/ornetwork 232. Wireless access points 436 and transceiver 434 are the sameas, or include the same functionality as, wireless access points 296 (or68) and receiver 254, respectively. In still other embodiments,controller 432 is modified to be able to act as a mesh network node 84in a mesh network 86 and carry out mesh network communication in any ofthe manners described previously.

Various alterations and changes can be made to any of the foregoingembodiments without departing from the spirit and broader aspects of theinvention as defined in the appended claims, which are to be interpretedin accordance with the principles of patent law including the doctrineof equivalents. This disclosure is presented for illustrative purposesand should not be interpreted as an exhaustive description of allembodiments of the invention or to limit the scope of the claims to thespecific elements illustrated or described in connection with theseembodiments. For example, and without limitation, any individualelement(s) of the described invention may be replaced by alternativeelements that provide substantially similar functionality or otherwiseprovide adequate operation. This includes, for example, presently knownalternative elements, such as those that might be currently known to oneskilled in the art, and alternative elements that may be developed inthe future, such as those that one skilled in the art might, upondevelopment, recognize as an alternative. Further, the disclosedembodiments include a plurality of features that are described inconcert and that might cooperatively provide a collection of benefits.The present invention is not limited to only those embodiments thatinclude all of these features or that provide all of the statedbenefits, except to the extent otherwise expressly set forth in theissued claims. Any reference to claim elements in the singular, forexample, using the articles “a,” “an,” “the” or “said,” is not to beconstrued as limiting the element to the singular.

What is claimed is:
 1. A location detection system comprising: a bedhaving a support surface and a wireless transceiver, the support surfaceadapted to support a person thereon, and the wireless transceiveradapted to wirelessly communicate with a plurality of access points of acomputer network, to transmit bed status information to the computernetwork, and to receive messages from the plurality of access points;and a controller adapted to generate a location estimate of the bedwithin a hospital based upon a signal strength of the messages receivedfrom the plurality of access points; wherein the wireless transceiver isfurther adapted to transmit the location estimate of the bed, asdetermined by the controller, to other beds.
 2. The location detectionsystem of claim 1 wherein the messages include a media access control(MAC) address for each of the access points.
 3. The location detectionsystem of claim 2 wherein the wireless transceiver wirelesslycommunicates with the plurality of access points in accordance withInstitute of Electrical and Electronics Engineers (IEEE) standard802.11.
 4. The location detection system of claim 1 further comprisingan infrared receiver adapted to receive an infrared signal from a fixedlocator positioned off of the bed, the infrared signal including alocator identifier unique to the fixed locator, and wherein the wirelesstransceiver transmits the locator identifier to one of the accesspoints.
 5. The location detection system of claim 1 wherein thecontroller is positioned on the bed.
 6. A location detection systemcomprising: a bed having a frame, a support surface adapted to support aperson thereon, and a wireless transceiver adapted to wirelesslycommunicate with a plurality of access points of a hospital computernetwork, the wireless transceiver adapted to transmit bed statusinformation to the hospital computer network and to receive messagesfrom the plurality of access points; a processing station locatedremotely from the bed and communicatively coupled to the hospitalcomputer network, the processing station adapted to access dataindicating locations of each of the plurality of access points; and acontroller on board the bed, the controller adapted to send to theprocessing station signal strength data of the messages, wherein theprocessing station generates a location estimate of the bed within ahospital based upon the signal strength data and the data indicatinglocations of each of the plurality of access points.
 7. The locationdetection system of claim 6 wherein the controller is adapted to sendthe signal strength data to the processing station using the wirelesstransceiver, and wherein the processing station includes map dataindicating locations of the access points within the hospital.
 8. Thelocation detection system of claim 7 wherein the hospital computernetwork is an Ethernet-based computer network.
 9. The location detectionsystem of claim 6 further comprising: an infrared transceiver supportedon the bed, the infrared transceiver adapted to transmit aninterrogation signal; and a plurality of locators positioned at fixedlocations, each of the locators adapted to wirelessly transmit a uniqueidentifier in response to the interrogation signal from the infraredtransceiver; and wherein the controller is adapted to send the uniqueidentifier to the processing station, the processing station beingfurther adapted to generate a location estimate of the bed within thehospital based upon the unique identifier.
 10. The location detectionsystem of claim 9 wherein the processing station is further adapted togenerate a location estimate of at least one of the access points basedupon the location estimate of the bed and the signal strength data. 11.The location detection system of claim 9 wherein the processing stationis adapted to access data indicating locations of each of the pluralityof access points, to generate a first location estimate of the bed basedupon the signal strength data and the data indicating locations of eachof the plurality of access points, and to generate a second locationestimate of the bed based upon the unique identifier.
 12. The locationdetection system of claim 11 wherein the processing station is furtheradapted to generate a third location estimate of the bed by combiningthe first and second location estimates.
 13. The location detectionsystem of claim 11 wherein the processing station is further adapted toforward at least one of the first and second location estimates to asecond processing station communicatively coupled to the hospitalcomputer network.
 14. The location detection system of claim 13 whereinthe processing station forwards the first location estimate to thesecond processing station if the bed is moving, and the processingstation forwards the second location estimate to the second processingstation if the bed is stationary and positioned adjacent to one of thelocators.
 15. The location detection system of claim 13 wherein theprocessing station forwards the first location estimate to the secondprocessing station if the bed has a brake off; and the processingstation forwards the second location estimate to the second processingstation if the bed has the brake on.
 16. The location detection systemof claim 6 wherein the processing station is adapted to transmit thelocation estimate of the bed to the bed.
 17. The location detectionsystem of claim 16 wherein the controller is adapted to transmit thelocation estimate of the bed wirelessly to another device.
 18. A personsupport apparatus comprising: a frame; a support surface adapted tosupport a person thereon; a wireless transceiver adapted to wirelesslycommunicate with a plurality of access points of a computer network, thewireless transceiver adapted to receive messages from the plurality ofaccess points; a sensor adapted to wirelessly communicate with a locatorpositioned at a fixed location within a hospital; and a controlleradapted to determine in which room of the hospital the person supportapparatus is located based upon data from the messages and to determinein which zone of the room the person support apparatus is located basedon communication between the sensor and the locator.
 19. The personsupport apparatus of claim 18 wherein the controller is further adaptedto transmit the room and zone to a processing station located remotelyfrom the person support apparatus and communicatively coupled to thecomputer network.
 20. The person support apparatus of claim 18 whereinthe controller determines the room based upon signal strength data ofthe messages when a brake on the person support apparatus is off. 21.The person support apparatus of claim 20 wherein the messages furtherinclude a media access control (MAC) address for each of the accesspoints.
 22. The person support apparatus of claim 21 wherein thewireless transceiver wirelessly communicates with the plurality ofaccess points in accordance with Institute of Electrical and ElectronicsEngineers (IEEE) standard 802.11, and the sensor is adapted to receivean electromagnetic signal from the locator.
 23. A person supportapparatus comprising: a frame; a support surface adapted to support aperson thereon; a first wireless transceiver adapted to wirelesslycommunicate with a plurality of access points of a computer network, thefirst wireless transceiver adapted to receive messages from theplurality of access points; a second wireless transceiver adapted towirelessly communicate with a locator positioned at a fixed locationwithin a facility, the second wireless transceiver adapted to receive aunique identifier from the locator; a memory in which map dataindicating a location of the locator is stored; and a controller adaptedto determine signal strength data of the messages, to wirelessly receivelocation data from another person support apparatus that is incommunication with at least one of the access points, and to generate alocation estimate of the at least one of the access points of thecomputer network based upon the unique identifier, the map data, thelocation data, and the signal strength data.
 24. The person supportapparatus of claim 23 wherein the controller is further adapted towirelessly transmit the location estimate to another person supportapparatus that is in communication with the at least one of the accesspoints.
 25. The person support apparatus of claim 24 wherein the firstwireless transceiver wirelessly communicates with the plurality ofaccess points in accordance with Institute of Electrical and ElectronicsEngineers (IEEE) standard 802.11, and the second wireless transceiver isan infrared receiver adapted to receive an infrared signal from thelocator.